KDB-GOM Series

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1. Specifications of the KDB-GOM series1.1 Kyungdong Boiler Product Features and Functions1.2 Specifications

2. Operating Types/Constructions/Schematic Diagram2.1 Operating Types2.2 Constructions of the Boiler2.3 Schematic Diagram of Operating

3. Equipment Protection and Personal Safety

4. Specifications and Functions of the Major Components4.1 Main Heat Exchanger4.2 Fan Assembly4.3 Circulation Pump4.4 Modulating Gas Control Valve4.5 3-Way Valve4.6 Expansion Tank4.7 Air Pressure Switch4.8 Hot Water Flow Sensor4.9 High Limit Sensor(Bimetal Type)4.10 High Limit Fuse(Fuse Type)4.11 Heating Temperature Sensor4.12 Ignition Transformer4.13 Power Transformer4.14 Domestic Hot Water Heat Exchanger4.15 Burner Assembly4.16 Nozzle Holder Assembly4.17 Wiring Diagram4.18 Main Controller

I. Technical Information

KDB-GOM Series

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THE KDB-GOMTHE KDB-GOMTHE KDB-GOMTHE KDB-GOMKYUNGDONG BOILER’S VARIABLE-CAPACITY-MULTI-PURPOSE

82%+ HYDRONIC HEATING SYSTEM

How does it work? The KDB-GOM provides 2 different heating functions that operate independently from the same boiler. One modeprovides space heating water to heat the home. The other mode provides a continuous circuit of hot water for domesticuse eg, bath, laundry, etc. Both circuits are separate and operate at different temperature ranges.

The space-heating water is controlled by the FR-5 thermostat. A special thermostat has been provided that enables theuser to either set the room temperature required of set the heating water temperature. In some cases this thermostat maynot be suitable for multi-system applications. (The installing contractor will make this determination and install suitablealternative controls.

The domestic hot-water is controlled by the user. Because the KDB-GOM is a multi-purpose design, it can provide hotwater on demand, there is no storage tank to hold hot water, when there is no use for it. The KDB-GOM will only producehot water when you use it : instantaneous. The modulating gas burner allows water to heat up as evenly as it is beingused. The KDB-GOM will continue to heat the water until the source or sources are shut off. This on-demand-use alsohelps to prevent water being held in the boiler for long periods of time.

IMPORTANT: A thermostatic mixing valve should be installed on the domestic water supply pipe to control the supply watertemperature and prevent any possibility of scalding.

Domestic hot water priority The GOM prioritizes bath water over space-heating water and will immediately stop producing space-heating water themoment a hot water valve is opened anywhere in the home. Once the valve has been turned off, the boiler will return tothe home-heating function again.

The seal-combustion processThe KDB-GOM is designed with a special sealed-combustion venting process. Both sides of the combustion process

(inlet oxygen and outlet carbon monoxide) are isolated from each other and are totally sealed-off from the air supply withinthe home. This reduces drafts, caused by infiltration, by as much as 82% making the KDB-GOM one of the safest, mostcomfortable and clean-burning boilers in the world.

1. Specifications of the KDB-GOM series1. 1 KyungDong GOM Product Features and Functions

A. Continuous Hot Water Its On Demand! KyungDong Boiler makes running-out-of-hot-water obsolete.

B. Everything Built-in Installs in half the time. We tried to think of all the parts and accessories you’ll need (plus a few you might haveforgotten) and built them into this multi-purpose hydronic heating system. You’ll spend less time driving to all the supplyhouses.

KDB-GOM Series

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C. Baked-in Beauty The high quality porcelain finish is bake on and keeps the exterior looking new and lustrous for years to come.

D. System Timer Save energy during times the home is unoccupied. Just set and activate the timer and leave. The unit turns off forpre-programmed intervals until you return.

E. Room Thermostat FR-5 Convenient and accurate, large digital display is easier to read, easier to use. Our new room thermostat gives theconsumer digital control over several heating function.

F. Performance Indicator With the use of the FR-5 electronic room thermostat, the (LED) will conveniently display the current operatingcondition of the unit such as temperature of heating water, room temperature, normal operation, etc.

G. Continuous-Discharge Ignition(C.D.I.) Direct ignition design requires no wasteful pilot burner and offers fuel savings.

H. Combustion Safety Protection If the unit fails to ignite after the “ON” switch is pressed, or if the flame is extinguished due to a gas shortage, theflame sensor will shut down the unit.

I. Always Balanced Operation Despite fluctuating wind conditions, changes in atmospheric pressure and other external disturbances, the

variable-speed combustion blower provides steady performance.J. Exhaust Safety Protection While operating, the exhaust-discharge fan is continuously monitored. The units will be immediately stopped toprevent fumes from entering the home if the wind gusts become excessive or if the flue exhaust has been clogged.

K. Smart Re-Start Should the unit’s flame fail due to strong winds or temporary low gas pressure, the unit will automatically restart. Incold weather climates, manual resets could cause freeze damage.

L. Safety Protection during Power Outages When the power fails, the gas is automatically shut down and the units are stopped.

M. Automatic Fill & Refill If for any reason the water level in the system drops to an unsafe level, makeup water will automatically fill to theappropriate levels.

N. Automatic Air Bleed Each unit has 2 built-in air bleed devices. One is manual and used for quick fill and venting convenience; the otheris air-activated and operates and automatically.

O. Removal of Impurities Each unit come equipped with a built-in, clearable, heavy duty, particulate water filter for trapping impurities andpreventing the clogging of pipes. This is a maintenance item.

P. Air-Ratio Controller Air ratio is monitored, adjusted and controlled prior to and during each operating cycle and will automatically adjustthe combustion rate. The air-ratio controller guarding against unsafe operating conditions also senses excessivegusts of wind filling the flue system.

Q. Proportional Temperature Control This control is designed to continually analyze water flow and usage while maintaining the outgoing water at aconstant, even temperature.

KDB-GOM Series

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1.2 Specifications

GAS WALL-MOUNT

FRONT View A

Full, Dual Function Heating Design. Natural and Propane Gas Models. B Pow er-Vent, 2-Pipe Combustion Process. Modulating Gas for Precision Temperatures. REAR Built-in Circulation Pump Assembly . View Built-in Ex pansion Tank. Quiet, Vibration-Free Operation. A Built-in Freeze Protection.

Digitally Controlled, Full-Logic Thermostat.

C Function SIDE View CENTRAL HEATING WATER (LEFT) Construction of Heat Exchanger

Heat Output (kcal/hr) 6,400 ~ 16,000 8,000 ~ 20,000 10,000 ~ 25,000 12,000 ~ 30,000 Max.Efficiency (%) 82 82 83 84

(wall) Temperature Setting Range () Maximum Working Pressure (kgf/cm2)

Pre-Charged Expansion Tank (liter) 6.5 6.5 8.5 8.5 Circulation Pump Freeze Protection Device

DOMESTIC HOT WATER Heat Output (kcal/hr) 6,400 ~ 16,000 8,000 ~ 20,000 10,000 ~ 25,000 12,000 ~ 30,000 Max.Temperature Setting () Continuous DHW production T = 25 (liter) 10.7 13.3 16.7 20.0

Continuous DHW production T = 33 (liter) 8 10.0 12.5 15.0 Continuous DHW production T = 40 (liter) 6.7 8.3 10.4 12.5

C Continuous DHW production T = 50 (liter) 5.3 6.7 8.3 10.0 SIDE View Maximum Working Pressure (kgf/cm2) (RIGHT) OTHER DATA

Gas Type Gas Consumption - LP (kg/hr) 1.58 1.98 2.48 2.97

(wall) Gas Consumption (natural gas) (kcal/hr) 19,000 23,700 29,700 35,600 Gas Inlet Supply Pressure (natural: kPa) (min - max) Manifold Pressure (kPa) 0.16 ~ 0.92 0.16 ~ 0.96 0.25 ~ 0.94 0.14 ~ 0.96

Usage (Heating & Hot Water) Water Storage Capacity (liter) 0.7 0.7 0.8 0.8 Power (volts/cycle) Power Consumption (watts) Ignition NOx Emissions (Ref:0%, O2 in flue gas natural gas, ppm)

E F G D Temp. of Exhaust Gas () WEIGHT AND DIMENSIONS

Net Weight (lbs) 31 31 39 39 BOTTOM A Physical Dimensions: Height (mm) 630.0 630.0 685.0 685.0 View B Width (mm) 485 485 525 525

C Depth (mm) 235 235 250 250D Connection: Gas Inlet 15A, 1/2" 15A, 1/2" 20A, 3/4" 20A, 3/4"E Connection: Heating Water Supply/Return

B F Connection: Domestic Hot Water Supply/Return (front) G Connection: Primary Power (AC220V-50Hz)

H Flue Diameter (Intake / Exhaust) (mm)

TOP H Specif ications subject to change without prior notif ication View ( wall )

N - 2865 PELLISSIER PLACE - WHITTIER, CA 90601 - (562) 463-0880

15A, 1/2"15A, 1/2"70 / 75

28 (less than)150 (less than)

20A, 3/4"

Dual

AC 220V-50Hz120 ~ 160

ELECTRONIC

80

17.5

Liquefied Petroleum (L.P.) or Natural Gas

0.98 ~ 2.45

40 ~ 803

Self PrimingThermistor

MODEL NUMBER Combo Boiler

Stainless Steel / Copper

161 GOM 201 GOM 251 GOM 301 GOM

w ith 1-Year on Parts.

KYUNGDONG BOILER SPECIFICATIONS

Controls Both Water Functions Separately . On-Demand Hot Water Deliv ery . Compact, Space-sav ing Design.

Limited Warranty on Heat Ex changer

---- KEY FEATURES Prov ides Hi-Temp Water for Heating the Home. Prov ides Hot Water for Bathing & Washing.

KDB - 161 / 201 / 251 / 301 GOM Residential Gas Hydronic Heating System

GAS FIRED, WALL-MOUNTED, MULTI-PURPOSE, HYDRONIC HEATING SYSTEMS MODEL RANGE : 16,000 ~ 30,000 kcal/hr

KDB-GOM Series

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2. Operating Types/Constructions/Schematic Diagram2.1 Operating Types

Item Specification

Installation Wall Mount Type

Flue Type Both Use FF and FE

Usage Both Use Heating and Domestic Water (Single Pipe, 2 Waterways)

Water Supply forHeating

Maintain normally at a constant water pressure by pressure reducing valve(Auto / Manual)

Control Method Proportional Control Method by MICOM

Heat Exchanger Type Single Dry Type (131/161/201GOM) and Single Wet Type (251/301/351GOM)

Combustion Method Air Intake Method by Semi-Bunsen Burner

Gas Flow Control Current Proportional Control Method by Thermistor

Heat ExchangeMethod of Hot Water

Heat Exchange Method : Indirect Heat Exchange by Secondary Heat Exchanger Heat Exchange Type : Plate Formed Brazing Heat Exchange Heat Exchange Circuit : Parallel Circuit

Ignition Method Continuous Discharge, Direct Ignition Method

Heating /

Domestic WaterChangeover

Heating Priority, Changeover to Domestic Water Circuit by 3-way Valve

Domestic Water Signal Detect Flow by Flow Switch

Motor : Condenser Type Casing : Engineering Plastic

Circulator Pump

Impeller and Shaft Coupled : Magnetic Type

Expansion Tank Type : Expansion Tank Volume:6.5Liter(161/201GOM), 8.5Liter(251/301GOM)

Pressure Reducing /Flow Limiting Controland Water Hammering

Prevention

Control Pressure Reduction/Flow Limit and Prevent Water Hammeringby Diaphragm

KDB-GOM Series

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2.2 Constructions of the Boiler

Model : KDB Model : KDB Model : KDB Model : KDB – 251 / 301 GOM 251 / 301 GOM 251 / 301 GOM 251 / 301 GOM

Model : KDB – 161 / 201GOM

KDB-GOM Series

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2.3 Schematic Diagram of Operating2.3.1 Schematic Diagram at the Heating Water Supply

High Limit Fuse

Fan Assembly

Heating TemperatureSensor

Hot Water Flow Switch

ModulatingGas Control Valve

Expansion Tank

Air Pressure Switch

Nozzle Holder Assembly

Burner Assembly

Flame Detector

Electrode

High Limit Sensor

②Main Heat Exchanger

Exhaust Duct

③ 3-Way ValveG

as In

let

Dom

estic

Wat

er O

utlet

Tap

Wat

er In

let

⑥ H

eatin

g Re

turn

④ H

eatin

g Su

pply

⑦ Heating Strainer

① Circulator Pump

Flue Exhaust

Heating Flow Sensor

Combustion Air Inlet

Domestic WaterHeat Exchanger

① Circulator Pump → ② Main Heat Exchanger → ③ 3-Way Valve → ④ Heating Supply

⑦ Heating Strainer → ⑥ Heating Return → ⑤ Room Heating(Heating Coil, Radiator)

KDB-GOM Series

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2.3.2 Controls of the Heating Temperature2.3.2.1 When the heating water temperature is selected

- Setting Temperature: 40 ~ 80 - To stop the run, turns the “HEATING WATER

TEMP.” dial to “OFF” position.

2.3.2.2 When the heating is controlled by the roomtemperature

- Setting Temperature: 10 ~ 40 - To stop the run, turns the “ROOM TEMP.” dial to

“OFF” position.

2.3.2.3 When the heating with the repetition time(TIMER)

- The timer sets the stop time between 0 to 4-hours.- Press the “TIMER” button, the boiler runs for 20-

minutes and stops for the time set by the timer.- The temperature of the heating water is

automatically set at 80 and the temperatureindicator displays the room temperature.

※ If the range of control has been exceeded due to the change in the set temperature or to abrupt change inflow, the set temperature will be reached through the proportional control with the delay of 30±3 seconds.If 83 is exceeded, the delay of 30±3 seconds will not be performed.

Control RangeSetting Temperature,“T” set ON OFF

Over 78 63±2.0 83±2.0

70 ~ 77 “T” set – (14±2.0) “T” set – (6±2.0)

60 ~ 69 “T” set – (12±2.0) “T” set – (6±2.0)

50 ~ 59 “T” set – (10±2.0) “T” set – (5±2.0)

Below 49 “T” set – (10±2.0) “T” set – (5±2.0)

KDB-GOM Series

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2.3.3 Schematic Diagram at the Domestic Water Supply

Fan Assembly

Heating TemperatureSensor

② Hot Water Flow Switch

ModulatingGas Control Valve

Expansion Tank

Air Pressure Switch

Nozzle Holder Assembly

Burner Assembly

Flame Detector

Electrode

High Limit Sensor

Main Heat Exchanger

High Limit Fuse

Exhaust Duct

3-Way Valve

Gas

Inlet

Dom

estic

Wat

er O

utlet

Tap

Wat

er In

let

Heat

ing R

etur

n

Heat

ing S

upply

Heating Strainer

Circulator Pump

Flue Exhaust

Heating Flow Sensor

Combustion Air Inlet

③ Domestic WaterHeat Exchanger

③ Domestic Water Heat Exchanger

Domestic Water Line Heating Water Line

Main Heat Exchanger

④ Domestic Water Outlet

② Hot Water Flow Switch

① Tap Water Inlet

3-Way Valve

Circulator Pump

Expansion Tank

KDB-GOM Series

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2.3.4 Controls of the Domestic Water Temperature2.3.4.1 Possible use of hot water in heating/not-at-home mode and hot water exclusive mode, according to theflow volume detection of the hot water sensor.

2.3.4.2 Indirect control of the hot water temperature based on the heating water temperature.

2.3.4.3 Control at 80 when using hot water during heating.

2.3.4.4 Control at 70 when not-at-home or hot water exclusive mode

2.3.4.5 Stand by after hot water use

when stopped after hot water use, the fan does not perform post purge and maintain the ON status for 90seconds.

the pump stops after the post purge (60 seconds)

when using hot water again and after the hot water sensor detects the flow volume

pre-ignition fuel supply flame detection post-ignition

return to the before-hot-water-use status 90 seconds after the use of hot water.

2.3.4.6 Combustion in progress while in stand-by for hot water (90 seconds) or after 12 seconds of the post purgetime ( while in heating mode after the hot water sensor if “OFF”). Hot water stand-by time in progress separately.

3. Equipment Protection and Personal Safety

A. Ignition Failure If the ignition fails, the gas supply is automatically cut off. An error code will appear as a flashing 2-digit code on the room

thermostat(models FR-5 only). The error codes are discussed in the troubleshooting section of the installation manual.

B. Flame Detection If the fails and/or the re-ignition attempt fails, the gas supply is automatically cut off. An error code will appear on the room

thermostat(models FR-5 only).

C. Power Interruption When the power is restored after a power failure, the boiler will automatically start and return to normal

operation(Manual reset is not required).

D. Excessive Air Pressure Occasionally an excessive gust of wind from outside may be forced into the flue pipe. The air-ratio control module

will detect these strong back-drafts. To prevent any products of combustion from re-entering the building through theopen flue, the gas supply will be automatically cut off. An error code will appear on the room thermostat(models FR-5 only).

E. Explosive Re-ignition Protection Abrupt, noisy startups and backfires are prevented by means of soft ignition, a trademark of our air-ratio controlmodule.

F. Overheat Protection Any overheating of the burners or heat exchanger will automatically shut down the supply of gas to the burners.

An error code will appear on the room thermostat(models FR-5 only).

G. Low Water-Level Safety Water levels in the heating pipes are continuously monitored to prevent the boiler from operating if there is no

water or a restricted flow through the piping. The boiler will automatically shut down and an error code will appearon the room thermostat(models FR-5 only).

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H. Automatic Water Fill Should the water level in the system drop too low, a sensor will automatically activate the re-fill circuit.

I. Freeze Protection During the heating season, a sensor inside the boiler will automatically detect and initiate safe heating cycles to prevent internal

equipment damage from occurring should freezing temperatures surround the boiler. Note ! - When there is no gas supplyavailable, the circulating pump will automatically start up to guard the pipes from freezing (available only in boilers equipped with acirculation pump).

J. Gas Pressure Control To prevent internal damage from rupture, each boiler is protected from occasional surges in gas pressure by a regulating governor

device located in the gas valve.

K. Short-Circuit Protection Any short-circuits occurring inside the boiler’s electrical circuit will immediately ‘blow’ the internal glass fuse(s)and automatically cut off the gas supply.

L. Lightening Protection Each boiler is specially grounded inside and out to protect against lightening strikes.

M. Combustion air flow control When the combustion airflow is disrupted due to a defective, obstructed or an abnormal back-pressure of theflue, the combustion is shut off safely.

N. Thermostat Control Failure Should the thermostat fail to function properly, as a safeguard, the boiler’s gas supply will be automatically shutdown.

KDB-GOM Series

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4. Specifications and Functions of the Major Components

4.1 Main Heat Exchanger

Item 161GOM 201GOM 251GOM 301GOM

Type Single Dry Type Single Wet Type

Structure Copper Fin＋Copper pipe Brazing

Function - For use of heating and hot water, absorb generated heat from main burner andthen transmit it to heating pipe and hot water heat exchanger.

Number of Heat Fin 72 Fin 80 Fin 106 Fin 112 Fin

Material & Dimension - Copper Pipe:C1220T-H(φ15.88).- Heat Fin:C1220P-1/4H(t=0.4)

Heat Exchange Method Instantaneous Method

KDB – 251 / 301 GOM

KDB – 161/201GOM

KDB-GOM Series

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4.2 Fan Assembly

Item 161GOM 201GOM 251/301GOM

Fan Type Phase Controlled Air Intake Fan

Motor Type Shading Coil Induction Motor Condenser Induction Motor

Blower Dimension(mm) φ100 X 40L X 45 Fin φ134 X 40L X 60 Fin

Function - Supply air needed for combustion and exhaust the remained gas before and aftercombustion in order to prevent explosion in advance.

Bell Mouth(mm) φ 60 φ 70 -

Rated Voltage AC 220V, 50Hz

Power Consumption Max.: 36.4 W, Min.: 14.0 W Max.: 75 W, Min.: 30 W

Casing ALDC12

Blower AL 5052Material

Venture ALDC12

KDB – 161 / 201GOM

KDB – 251 / 301GOM

KDB-GOM Series

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4.3 Circulation Pump

Item All GOM models

Pump Type Magnet Type

Motor Type Single Phase, 2 Pole Induction Motor

Function

- Transmit the absorbed heat from main heat exchanger to heating pipe bycirculating heating water when use heating.

- Transmit the absorbed heat from main heat exchanger to hot water heatexchanger by circulating heating water inside of boiler when use hot water.

Maximum Pump Head 10M(at 0 gal/ min )

Rated Voltage AC 220V, 50Hz

Power Consumption 90 W

Condenser Capacity 2.5

Weight 2.45 kg

KDB-GOM Series

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4.4 Modulating Gas Control Valve

Item All GOM models

Model No. UP 33 –06 (TIME CO.)

Rated Voltage AC 220V, 50 / 60Hz

Power Consumption 8 W

Function

Controls the flow of gas supply by the current value received from maincontroller.

Cut off the gas to prevent danger by the signal of sensor when happen troublescaused by improper combustion.

Magnet Valve Proportional Valve

Schematic Diagram

SV1(UV3)

SV2(UV3)

PV(UP2)

(SV1) (SV2) (PV)

Secondary pressureAdjust Screw

Gas flow diagram

KDB-GOM Series

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4.5 3-Way Valve

Item All GOM models

Rated Voltage AC 220V, 50 / 60Hz

Power Consumption 3 W

Body Material NYLON 66

Function

- Block the passage of heating water by the flow detection in flow switch and flowheating water into the hot water heat exchanger when use hot water, and lead toexchanging the heat of hot water with heating water in the hot water heatexchanger. (When stop using hot water, the water passage is changed over tothe way of heating pipe automatically.)

Heating → Hot Water 10 ± 2 secOperating Time

Hot Water → Heating 10 ± 2 sec

Wire Identification RED : Heating, BLUE : Hot Water BLACK : Common

Model

Motor Speed 2.5 ~ 3 RPM

Direction of MotorRotation CCW

KDB-GOM Series

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4.6 Expansion Tank

NO. Part Name Material Remarks

1 Body SBHG1 , 2.0t

2 Bracket SBHG1 , 2.0t

3 Diaphragm BUTYL , 2.0t

4 Nipple S10C , PF3/8”

Item KDB – 161 / 201GOM KDB – 251 / 301GOM

Volume 6.5 Liter 8.5 Liter

Body Material SBHG 1

Charging Gas Nitrogen

Charging Pressure 1.0 kg/cm2 (14.2 psig)

Function

Vent the generated air in the heating pipe.

Absorbs pressure generated in the pipe by the expansion of heating water due toincreasing temperature of heating water.

Maintain the water volume in the boiler at a constant by low water level sensor.

Nitrogen gasCharging point

KDB-GOM Series

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4.7 Air Pressure Switch

Item All GOM Model

Electric Rating 0.1A –125V AC, 0.1A –30V DC (Micro Switch)

Type Differential Pressure Type (Vertical Type), Normal Close Type

Body Material Nylon 66 (GF 30%)

Function - Stop the combustion safely and automatically by monitoring the high pressureor the adverse wind in the flue.

Contact Arrangement

ON more than 2.0 mmH2OON / OFF OperatingPressure OFF 7.0 ± 2 mmH2O

Reference- Normal Close Type : The contact is always connected, and if the wind

pressure switch is operated by adverse pressure, this contact is opened andstop the combustion in the boiler.

P3 (COM)

P1 (NC)

P2 (NO)

KDB-GOM Series

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4.8 Hot Water Flow Switch

Item All GOM models

Body Material Nylon 66 (GF 30%)

ON 2.3 ± 0.3 liter / minOperating Flow

OFF 1.5 ± 0.5 liter / min

Installation Type Horizontal Installation

Function

- When use hot water, detect the flow of hot water and transmit the signal tocontroller, and operate 3-way valve to usable hot water.

- Reduce the pressure of discharging hot water in case of high water pressurearea (water supply pressure : more than 1.5 kgf/) and maintain the optimumcondition of hot water use through flow limited by reduced pressure.

Reducing PressureCapability P1 : 0.3 ∼ 10 kgf/ → P2 : 0.3 ∼ 3.0 kgf/

Contact Rating 10 VA (W)

Maximum Contact Current AC, DC 0.5A

Contact Resistance less than 300 mΩ

수동 물보충

KDB-GOM Series

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4.9 High Limit Sensor (Bimetal Type)

Function

- When the bimetal plate in the high limit sensor detects the increase in theheating water temperature or in causing surface temperature, it istransformed to move the shaft and to let the contact “OFF”

- The “OFF” signal from the high limit sensor is sent to the controllers so thatthe check lamp on the room thermostat comes “ON” and the failure codeNO. 16 is displayed on the temperature indication. When the running isresumed, only the check lamp is kept “ON”.

- In case of reduced discharge of combustion exhaust or overheat of heatexchangers, the high limit sensor automatically cut off the gas control valve toclose it when the send the sensed the temperature of the heat exchangerreaches 95 or higher. The check lamp on the room thermostat is lit andfailure code NO. 1 is indicated on the indication panel.

Model MS-1, Manual Reset

Type Bimetal Type

Operating Temp. 95 Structure

Recovery Temp. 80

Voltage Rating 125 ~ 250 VElectric Rating

Current Rating 15 A

[Automatic, MS-1]

KDB-GOM Series

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4.10 High Limit Fuse (Fuse Type)

Function

- In case of abnormal overheat of heat exchanger, the temperature of sensorpart will be more than 195 , high limit fuse will cut off the power ofmodulating gas control valve to close the modulating gas control valve andsecure the safety.

- Check lamp will on in the room thermostat and failure code # 03 will beindicated.

Type Fuse Type

Structure

Operation Temp. OFF point: 195

Electric Rating Resistance 61.1 Ω at 20

KDB-GOM Series

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4.11 Heating Temperature Sensor

Item All GOM models

Model No. DKS - 902ET - 330C

Resistance R50 = 3.485 ± 3%

B Constant R0 / R100 = 3449 K ± 1%

Thermal Radiation Constant 0.7 mW /

Thermal Time Constant Within 10 seconds

Function

- Detect the temperature of heating water and transmit the signalto main controller. The main controller controls the flow of air /gas needed for achieving and maintaining the settingtemperature.

KDB-GOM Series

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4.12 Ignition Transformer

Function - Electric energy provides high voltage and current to the main burner forignition of gas.

Primary Rating AC 220 V , 50 / 60 Hz

Secondary Rating 19 kVo-p±2Power Requirement

Secondary Current 7 mA±2

Casing Non-Combustible ABSStructure

Cable Silicon

KDB-GOM Series

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4.13 Power Transformer

Function - Supply the power source to boiler.

Input Rating AC 220 V , 50 / 60 Hz

AC 220 V # 8-BLACK, # 9-GRY

AC 34.0 V # 2-RED, # 6-RED

AC 18.4 V # 1-ORANGE, # 5-BLUE

Power RequirementOutput Rating

AC 12.0 V # 4-WHITE, # 7-BROWN

Casing Non-Combustible ABSStructure

Cable Silicon

KDB-GOM Series

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4.14 Domestic Hot Water Heat Exchanger

Item 161GOM 201GOM 251GOM 301GOM

Material STS 304

Capacity 10 Pieces 12 Pieces 16 Pieces 18 Pieces

Function- When use hot water, supply the heating water heated in main heat exchanger to hot water

heat exchanger and heat-exchange water (water supply) with heating water supplied inhot water heat exchanger to be usable hot water.

Domestic WaterOutlet

HeatingSupply

Tap Water Inlet

HeatingReturn

KDB-GOM Series

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4.15 Burner Assembly

Item 161 / 201GOM 251 / 301GOM

Quantity of Secondary Nozzle 10 EA 15 EA

Material of Secondary Nozzle ALSTAR

Slit (Flame Holder) Material STS 430

Front Bracket SBHG 1

Rear Bracket STS 430

Function - Supply heat sources by mixing and combusting the supplied gas andair.

KDB-GOM Series

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4.16 Nozzle Holder Assembly

Item 161GOM 201GOM 251GOM 301GOM

Quantity of Primary Nozzle 10 EA 15 EA

Material of Primary Nozzle C3602 BD

Material of Nozzle Holder A6063S

LNG φ1.33 φ1.46 φ1.37 φ1.50Diameter ofNozzle(mm) LPG φ0.92 φ1.06 φ0.95 φ1.06

Function - Supply gas needed for combustion according to demands.

Secondarygas pressuremeasuring hole

KDB-GOM Series

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4.17 Wiring Diagram4

NO Function NO Function

1, 3 Gas Valve 1 7, 12 Ignition Transformer

2, 3 Gas Valve 2 8, 12 3-Way Hot Water

4, 11 AC 220V 9,13 3-Way Heating

5, 6 Circulation Pump 10 Ground

NO Function NO Function

1, 11 Water Filling 9, 20 Room Thermostat

2, 12 Fan

3, 13 Control Voltage

4 RPM Power Source 14 RPM Input

5, 15 Heating Temp.Sensor

15 RPM Ground

6 16 Flame Detector

7, 20 Air PressureSwitch

17 Heating Flow Sensor

8, 20 Hot WaterFlow Switch

18, 19 Overheat

NO Function NO Function

1,5 AC 20V 4,7 AC 12V

2,6 AC 40V 8,9 AC 220V

3 AC 200V

4.17.3.3 21 Pin Wiring Connecting Diagram

4.17.3.2 9 Pin Wiring Connecting Diagram

4.17.3.1 13 Pin Wiring Connecting Diagram4.17.3 Wiring Connecting Diagram

4.17.1 Fault repair codes (room thermostat, FR-5)

NO ON OFF

1 Trial Run Normal2 Forced Max.

CombustionNormal

3 Forced Min.Combustion

Normal

4 FE FF

5 L.P. Gas Natural Gas

6 Close-Air Type Open Tank System

7 50 Hz 60 Hz

NO 161GOM 201GOM 251GOM 301GOM

8 OFF OFF ON OFF

9 ON ON OFF OFF

10 ON OFF ON ON

4.17.2 DIP S/W Setting on Main ControllerFNDNo.

Problems FNDNo.

Problems

01 Overheat 10 Air pressure failure

02 Low water level 11 Water level detection failure

03 Ignition failure 12 Flame failure in combustion

04 Flame sensor (Lower gas pressure)

13 Heating water switch failure

05 Heating sensor wire disconnected

14 Gas alarm(optional)

06 Short circuit of heating sensor 15 MICOM failure

07 Hot water sensor wire disconnected 16 Mechanical overheat

08 Short circuit of hot water sensor 17 DIP switch setting error

09 Fan R.P.M. failure 18

KDB-GOM Series

- 29 -

4.17.3 Wiring Diagram

WHT : WHITEORG : ORANGE

AC34VAC220V

AC18.4V

IGNITION TRANS

LEGEND

GRY : GRAYRED : REDBLK : BLACK

BLK2)BRN: Secondary valve2)BLK: Currency

.

.

Modulation

YEL : YELLOWBLU : BLUE

1)BLU : Primary valve

TIME UP 33-06GAS VALVE

BLU

BLK

EV 1BLU

BLURED

.

.

BRN

BRNEV 2

HIGH LIMIT FUSE

2)BLK,BLU : HOT WATER

1)BLK,RED : HEATING WATER

THREE WAY VALVE

.

.

GRNRED

BLKBLU

EARTH

AIR PRESSURE

: DC 5V : DC 5V

SWITCH

INPUT SIGNAL

HEATING FLOW SW

ITCHINPUT SIGNAL

: DC 20V

THERMOSTATINPUT SIGNAL

ROOM

: DC 5V

HOT WATER

FLOW SW

ITCHINPUT SIGNAL

WHT

RED

SUPPLY POWER

BLKW

HT

FUSE , 3A - 2EA

PUMP POW

ER TRANSFORMER1)W

HT : AC 5VBLK

BLK

INPUT SIGNAL : AC 200V

3)BLK : Ground2)RED : DC 12V

FLAMEDETECTOR

EARTH

SUPERVISIONFAN ROTATION

BLKRED

BLK

: DC 20V

YELYEL

GRN PREVENTION

INPUT SIGNAL

OVERHEAT

SKYSKY

BLUBLU

ORGBLK

REDGRY

AC220V

: DC 5V

TEMPERATUREHEATING W

ATER

INPUT SIGNALW

HT

FANRED

REDBLK

BLURED

REDBLU

: DC 5 - 20V

68

F

50

176

38699

4F

2

Hrs

10

140

104

ORGORG

ALARM WIRE

INPUT SIGNAL

GAS LEAKAGE

BLKBLK

RED( - )

(+)

[13 PIN]

.

.

12

34

GRN : GREENBRN : BROWN

97

810

11

[9 PIN]

[21 PIN]

20

BLUAC18.4V

REDBRN

YELW

HTAC34V

AC12VAC200V

AC12V

56

12

34

1213

58

67

9

12

34

67

85

1311

1214

1517

1618

19

91021

KDB-GOM SERIES WIRING DIAGRAM

AC220V, 50/60Hz

220VAC 50HzAC220V, 50Hz

AC220V, 50Hz

AC 220V, 50/60Hz

AC 220V, 50/60Hz

Operating Temp. : 156 °C

KDB-GOM Series

- 30 -

4.18 Main Controller

Voltage , Frequency AC 220V , 50 / 60 Hz

Voltage Range +10% to –15%

Ambient Temp. -15 to 70Electric Spec.

Ambient Humidity 45 – 90 %

Structure Casing ABS

Model KDC – 208-1M

4.18.1 DIP switch setting on main controller

4.18.2 Functions of Main Controllers4.18.2.1 Pre-Purge

When the boiler operates, the function is to operate blower (fan) first and exhaust the remained air in the combustionchamber before combustion starts, in order to prevent from immoderate ignition. Pre-Purge time is by achieving the fan’slight-up RPM ± 200 rpm with more time than 4 ± 1 seconds.

4.18.2.2 Pre-Ignition After Pre-Purge, the function is to operate ignition transformer previously in order to light up easily before supplying thefuel (gas) for combustion. Pre-Ignition time is from ON time of ignition transformer till ON time of fuel supply device (gasvalve 2).

DIP Switch adjust partMax. adjust screwfor secondary gaspressure

NO ON OFF

1 Trial Run Normal

2 Forced Max.Combustion Normal

3 Forced Min.Combustion Normal

4 FE FF

5 L.P. Gas Natural Gas

6 Close-Air Type Open Tank System

7 50 Hz 60 Hz

NO 161GOM 201GOM 251GOM 301GOM

8 OFF OFF ON OFF

9 ON ON OFF OFF

10 ON OFF ON ON

KDB-GOM Series

- 31 -

1 ± 1 second

4.18.2.3 Post- Ignition The function is to keeps operation of ignition transformer until flame detector monitors and combustion flame is stableafter fuel supplied and ignited. Post-Ignition time is from the time of fuel supply till OFF time of ignition transformer.

4 ± 2 seconds

4.18.2.4 Post-PurgeThe function is to exhaust the remained gas of combustion after flame extinguished when boiler stops. Post-Purge time isfrom OFF time of fuel supply device till OFF time of fan.

Blower : 20 ± 2 seconds / Pump : 60 ± 6 seconds

4.18.2.5 Safety Shut-Off (No Light-Up)The function is to stops fuel supply for safety when the flame signal isn’t detected even though boiler’s blower is operated,and Pre-Purge, Pre-Ignition done and fuel supplied. Safety shut-off time is from ON time of fuel supply device till OFF timeof fuel supply. At that time, ignition transformer is also OFF.

3 ± 1 seconds

4.18.2.6 Boiler Stopping by Safety Shut-Off If fuel supply and ignition transformer is OFF by the function of safety shut-off, the restarting operationrepeats (operation of Pre-Purge, Pre-Ignition, Fuel supply, Flame detection, etc by a series of control sequence) andcounts their cycle. If the number of safety shut-off is 3 times in series, transmits ignition trouble signal to the temperaturecontroller and fan is OFF after Post–Purge done. (Only if water temperature in the pipe is more than 80 ± 2.0, fan andpump operate.)

4.18.2.7 Misfire (Flame Extinction or No Flame Detection) During CombustionWhen misfire is monitored during combustion, stops fuel supply and performs the ignition operation by re-starting function(Pre-Purge, Pre-Ignition, Fuel supply, Flame detection, etc by a series of control sequence) and counts their cycle. If thenumber of fire loss is 10 times, fuel supply device is OFF and transmits the misfire signal to temperature controller, andthen fan is OFF after Post-Purge done. (Only if water temperature in the pipe is more than 80 ± 2.0, fan and pumpoperate.)

4.18.2.8 Flame Detection during Pre-Purge (The Early Pseudo Flame) When monitored flame signal during Pre-Purge time, stops to be progress even though Pre-Purge done, and transmitsthe pseudo flame signal to temperature controller after checking continuously for 3 ± 1 seconds. Post-Purge performs inseries, and release automatically when pseudo flame is disappeared and then is returned the function as before. (Only ifcirculation pump operate continuously until release the pseudo flame.)

4.18.2.9 Combustion Stop / Flame Detection during Standby (The Last Pseudo Flame)When extinguishes by stopping fuel supply and performs Post-Purge, transmits the pseudo flame signal to thetemperature controller if flame isn’t extinguish actually or the flame signal is monitored during waiting combustion and isn’tdisappear within 3 ± 1 seconds. Post-Purge performs in series, and release automatically when pseudo flame isdisappeared and then is returned the function as before. (Only if circulation pump operate continuously until release thepseudo flame.)

4.18.2.10 Low Water Level, Normal Water Level When the power of boiler is ON, monitors always water level from low water level and normal water level sensor. Ifmonitors low water level that water is not enough in the boiler, the boiler stops running. Auto water filling valve is ON andfilling a boiler with water after pump is OFF, and transmits low water level signal to the temperature controller. (If the boileris filled with water by normal water level, the signal is released automatically and returned the status as before.) Closed airtype boiler doesn’t use normal level sensor and the heating water flow switch is attached on the low water level sensor. Ifpump operates and heating water flow switch is ON within 6 ± 1 seconds, consider normal water level, and if heatingwater flow switch is not ON, transmit abnormal status signal to temperature controller and pump is OFF and thenmaintain this condition until restarting. (Only if water temperature in the pipe is more than 80 ± 2.0, fan operate.)

KDB-GOM Series

- 32 -

4.18.2.11 Water Level Sensor Trouble (Opened Air Type) If monitors water level that there are water at the normal water level sensor and no water at the low water level sensor,consider the trouble of normal water level sensor or low water level sensor, and operates immediately a serial of operationas same condition of low water level. (Only if water temperature in the pipe is more than 80 ± 2.0, fan operate.)

4.18.2.12 Heating Temperature Sensor Trouble If finds the trouble of disconnection / short-circuit by checking heating temperature sensor as long as the power of boileris ON, the boiler is stopped (The burner stops and the pump / blower operate continuously, and stop the pump / blowerafter temperature sensor is returned to normal and check water temperature to be less than 80 ± 2.0 in the pipe.) andthe failure status of sensor is indicated in temperature controller.

4.18.2.13 Combustion Indication Combustion indication in the temperature controller displays by the presence of flame signal. (Not by the presence offuel supply)

4.18.2.14 Air Pressure Switch Air pressure switch is always ON regardless of blower. When air pressure is excessive, aind pressure switch is OFFand the boiler is stopped and the abnormal status of air pressure is transmitted to the temperature controller. Bloweroperates continuously and release automatically when return to normal state. (Only if water temperature in the pipe ismore than 80 ± 2.0, pump operates. The abnormality of RPM isn’t monitored in the abnormal status of wind pressure.)

4.18.2.15 Gas Leakage Alarm When the gas leakage signal is input from outside, the boiler is stopped and blower operates to ventilate air. When thegas leakage signal is released, the abnormal status is disappeared automatically and then returns to the status as before.(Only if water temperature in the pipe is more than 80 ± 2.0, pump / blower operate.)

4.18.2.16 Pump Trouble Water level control method of the closed air type boiler is decided by the input presence of flow switch within 6 ± 1seconds after pump is ON. When there is no signal of flow switch within 3 ± 1 seconds, delay Pre-Purge by 6 ± 1seconds. When the signal is, operate normally. If flow switch is ON continuously more than 15 ± 3 seconds before pumpoperates, consider the trouble of pump or flow switch and transmit abnormal status to the temperature controller. Pump isOFF and maintains this status until re-operate the temperature controller. (Only if water temperature in the pipe is morethan 80 ± 2.0, fan operate.)

4.18.2.17 Time Multiple Function When Control Heating When heating combustion operates continuously at a steady heating value by heating command of the temperaturecontroller, calculate average heating value and is converted into running time / stop time according to heating value. Andthen maintain the stopping state (same as outdoor state) for regular time after running combustion for regular time. Ifchanged heating command or setting temperature in the temperature controller or operated hot water combustion, etcexcept heating function within heating running time or forced stop time, the time should be always initialized. (Only in hotwater combustion, it doesn’t stop function.)

4.18.2.18 MICOM Trouble As the part of deciding trouble inside of the controller, considers that there is trouble of MICOM when external ACpower of 50/60Hz isn’t monitored, stops all output and transmits trouble status to the temperature controller and thenmaintains the current state until re-operate the temperature controller. (If water temperature in the pipe is more than 80 ±2.0, pump operate.)

4.18.2.19 Heating Control when Hot Water Use Proportional control uses the indirect control method of hot water temperature by heating water temperature and hotwater temperature is as follows.

In case of FR-5 use, water temperature in the pipe is 80 when choose heating, and is set 70 when chooseoutgoing and hot water .

4.18.2.20 Heating Temperature Control The temperature of heating water at the discharge may be set in the range of 30~80±4.0 at the room thermostat. Ifthe temperature of the heating water is lower than 83, the ratio control(PID) will be performed in accordance with thespecified procedures.

If the range of control has been exceeded due to the change in the set temperature or to abrupt change in flow, the settemperature will be reached through the proportional control with the delay of 300±15 seconds.(If 83±4.0 is exceeded,the delay of 30±3 seconds will not be performed.)

KDB-GOM Series

- 33 -

ON/OFF Control RangeSet Temperatures (“T” set)

ON OFF

80 “T” set - (18±2) “T” set - (5±2)

70 ~ 77 “T” set - (14±2) “T” set - (7±2)

60 ~ 69 “T” set - (12±2) “T” set - (6±2)

50 ~ 59 “T” set - (10±2) “T” set - (5±2)

40 ~ 49 “T” set - (8±2) “T” set - (4±2)

30 ~ 39 “T” set - (6±2) “T” set - (3±2)

If the combustion is delayed due to the temperature increase as above, the pump will be continuously run and theresumption of combustion will be delayed for 300±30 seconds. (If the combustion stops at 85, the forced delay of 300seconds will not be executed.) If other functions than the heating, such as a different function or change in the set temperature, is performed during theheating time or forced stop time, the time should be changed to the initial value.(In the case of heating domestic hot watersupply, the boiler will not be stopped.)

4.18.2.21 Re-Use Standby after Use Domestic Hot Water When hot water flow switch is OFF by stopping use of hot water, fuel supply stop. Fan doesn’t perform Post-Purgecaused by stopping fuel supply and maintains ON status for 90 ± 9 seconds. If hot water flow switch is ON within this time,performs pre-Ignition, fuel supply, flame detection, and Post-Ignition. And return the status as before when expires 90 ± 9seconds after using hot water. Only if the heating signal is input in the temperature controller during hot water standby (90 ± 9 seconds) or after hotflow switch is OFF, turn immediately to heating. At this time, combustion should start always from the beginning aftercombustion is OFF, and Post-Purge time is 15 ± 3 seconds and hot water standby time progress separately.

4.18.2.22 Freezing Prevention When heating water temperature is lowered less than 10 ± 2.0, circulation pump operates for 30 ± 2 seconds by theinterval of one hour. If circulated water temperature is lowered less than 6 ± 2.0, operates circulation pump and startscombustion for freezing prevention after output of freezing running in temperature controller. When the heating watertemperature is more than 21 ± 2.0, the circulation pump and combustion stop.

4.18.2.23 The Number of Fan Rotation Trouble The RPM signal monitors after running fan and the related status is indicated in the temperature controller as follows.

- After reaching within ignition rpm ± 200rpm during ignition, ignition is started by controlling gas valve. If it doesn’t reachwithin 13 ± 2 seconds, consider as one time failure of ignition. When re-ignition is performed and it doesn’t reach for 3times in series within 13 ± 2 seconds, stop the ignition. After perform purge for 15 ± 2 seconds, start re-ignition again.(Only if repeats for 10 times of the above operation and doesn’t ignite, consider as the number of rotation trouble.)

- If ignite normally and progress the combustion, initialize the count of above operation.- If the number of rotation maintains less than 400 ± 200rpm or more than 3200 ± 200rpm for 12 ± 1 seconds during

normal combustion, consider as the RPM trouble.- When the RPM trouble is happens by the above mention, re-check trouble of blower for 30 ± 3 seconds after indicating

first the trouble status in the temperature controller. If decide as normal status (1000 ± 200rpm), release it automaticallyand return to normal status.

4.18.2.24 Bimetal (Mechanical Type) Overheat Control When overheat signal is monitored continuously for 1 ± 1 second from mechanical overheat sensor during combustionand stopping, transmits bimetal overheat status to the temperature controller and safety shut-off performs. Fan andcirculation pump operate continuously and stop when heating water temperature is less than 80 ± 2.0.

4.18.2.25 DIP Switch Setting Trouble The voltage of wind pressure switch is always monitored during combustion and stopping of the boiler, and it iscompared with current setting of DIP switch. When finds trouble, indicates trouble status in the temperature controller andstops combustion. (Only if set normal status, release automatically.)

KDB-GOM Series

- 34 -

4.18.2.26 Test Operation Function- It is priority of the set function of DIP switch.- Pump operates for 2 hours. In case of open type, operate continuously after auto water filling when low water level ishappens.- If releases test operation by manipulating DIP switch in standby status after performing test operation and sets again,initializes test operation function and starts test operation.- When low water level (pseudo flame) happens in case of closed air type, releasing automatically by the interval of oneminute and progresses continuously.- When flow switch is ON in case of closed air type, stops pump and checks trouble.- When DIP switch sets test operation, the power lamp flickers by repetition of ON for 1 second and OFF for 1 second.

4.18.2.27 Forced Maximum / Minimum Combustion Function- When change-over switch sets to forced Max or forced Min, combusts by the set Max or Min according to the capacity

of the boiler after normal ignition. (PID control doesn’t.)- When DIP switch sets for both forced Max and Min at the same time, combusts by forced Min.- During combustion of forced Max / Min, operation of stopping time isn’t performed.- If the test operation is ON in status of forced Max/Min operation, the function of forced Max / Min operation isn’t work.

4.18.2.28 Fault repair codes(room thermostat, FR-5)FND No. Problems FND No. Problems

01 Overheat 10 Air pressure failure02 Low water level 11 Water level detection failure03 Ignition failure 12 Flame failure in combustion

04 Flame sensor (Lower gas pressure) 13 Heating water switch failure

05 Heating sensor wire disconnected 14 Gas alarm(optional)06 Short circuit of heating sensor 15 MICOM failure07 Hot water sensor wire disconnected 16 Mechanical overheat08 Short circuit of hot water sensor 17 DIP switch setting error09 Fan R.P.M. failure 18

4.18.2.29 Current Proportional Range Compensation- Maximum current change by adjusting variable resistor for maximum current compensation.- Current compensation range can be variable more than ± 20mA of maximum current.

4.18.4.30 The Others- Heating flow switch is used to monitor water level of closure type (closed air type).- Power lamp is always lit in the condition of power ON and flickers by the repetition of ON for 0.5 second and OFF for 0.5second in the abnormal condition.

4.18.2.31 Secondary Gas Pressure according to Capacity of Boiler (mmAq)Model High Load Low Load

NG 104 20KDB – 161 GOM

LP 170 20

NG 104 20KDB – 201 GOM

LP 150 30

NG 104 20KDB – 251 GOM

LP 165 38

NG 106 20KDB – 301 GOM

LP 156 30

KDB-GOM Series

- 35 -

1. Precautions before installation1.1 Shipping from factory1.2 Choosing the best location1.3 Methods of installation1.4 Check the kind of gas1.5 Precautions for installation

2. Identifying the components of the boiler

3. Installation of water piping4. Installation of the flue

4.1 PVC Venting Method4.2 Flue pipes used for Standard Flue Kit models

5. Gas piping connections

6. Installation of the room thermostat6.1 Choosing the Best Location6.2 Installation

II. Installation of Boiler & Accessory

KDB-GOM Series

- 36 -

WARRANTY WILL BE CONSIDERED VOID IF THIS EQUIPMENT IS INSTALLED BY ANYONE OTHER THAN A

QUALIFIED, TRAINED AND LICENSED (WHERE APPLICABLE ) HEATING TECHNICIAN.

KYUNGDONG BOILER CORPORATION IS NOT RESPONSIBLE FOR PROBLEMS OR DAMAGE CAUSED BY IMPROPER

INSTALLATION INCONSISTENT WITH THIS MANUAL.

THE INSTALLING CONTRACTOR MUST INSTRUCT THE OWNER ON THE FULL OPERATION OF THIS PRODUCT.

THE INSTALLING CONTRACTOR MUST GIVE THE OWNER THE APPORPRIATE WARRANTY CERTIFICATE AFTERTHE INSTALLATION HAS BEEN COMPLETED.

1. Precautions before installation1.1 Shipping from factory The units are released from our facility specially packaged to prevent handling damage and contamination in transit.Dropping or throwing the boilers or moving them while outside of their shipping container may cause damage orinternal contamination by any moisture remaining after testing. Do not stand the boilers up by resting on theconnections piping.

1.2 Choosing the best location Never locate the unit outdoors,

Such as an open porch or patio or exposed to the wind, rain snow and cold temperature.Special consideration must be given to where the venting will terminate outdoors.

Do not locate the unit in an equipment room that has an exhaust fan. Install the unit securely on any non-combustible wall that is capable of supporting the 40 kg weight of this

equipment. Maintain an 150mm clearance to the left and right of unit including 150mm clearance in front of the unit for safety

inspections and future access. Do not install unit in an underground or semi-underground location unless using the model FF or designated

concentric flue kit for KDB-GOM models. When installing the unit, consideration must be given to the proper location. The location selected should be as

close to the vent pipe termination outside the building, and as centralized with the water piping system aspossible.

A minimum clearance of 100mm must be allowed for access to replaceable parts such as the thermostats, drainvalve and relief valve.

As the gas boiler is to be installed indoors, they shall not be installed outdoors, such as in the porch. Do not install boiler on combustible wall in a high humidity location.

There is a risk in using fuel burning appliances in rooms or areas where gasoline, other flammable liquids or enginedriven equipment or vehicles are stored, operate or repaired. Flammable vapors are heavy and travel along the floorand may be ignited by the igniter or main burner flames causing fire or explosion. Some local codes permit operation ofgas appliances if installed 18-inches or more above the floor. This may reduce the risk if location in such an area cannotbe avoided. Flammable items, pressurized containers or any other potential fire hazardous articles must never be placed on oradjacent to the boiler. Open containers of flammable material should not be stored or used in the same room with the boiler.

1.3 Methods of installation The units must be firmly secured on the wall, which can sufficiently hold the unit weight. Exhaust vent pipe has a maximum length of 5.0M with up to 3-90° elbow. Vent pipe must be angle 2-3° toward

the boiler to return condensate. The units should be grounded to prevent electric shock.

1.4 Check the kind of gas Check if the gas indicated on the rating plate is being used. If not, change the nozzle

by consulting the service center or dealers.

KDB-GOM Series

- 37 -

CONVERSION OF THIS APPLIANCE FROM NATURAL GAS TO PROPANE OR PROPANE TO NATURAL GASCAN ONLY BE PERFORMED by a QUALIFIED TECHNICIAN.

1.5 Precautions for installation Piping for heating and hot water should be cleaned before connecting to the unit.

Lime scale accumulation can reduce the life of the equipment, reduce efficiency and waste fuel. Boiler failure due tolime or scale buildup voids the warranty.

Check the metal tag on the relief valve and compare it to the heater’s rating plate. The pressure rating of the relief valvemust not exceed the working pressure shown on the rating plate of the heater. In addition, the hourly heat capacityrated temperature discharge capacity of the relief valve shall not be less than the input rating of the heater. NO VALVEIS TO BE PLACED BETWEEN THE RELIEF VALVE AND TANK. DO NOT PLUG THE RELIEF VALVE. The drain line connected to this valve must not contain a reducing coupling or other restriction and must terminatenear a suitable drain to prevent water damage during valve operation. The drain line shall be installed in a manner toallow complete drainage of both the valve and line. DO NOT THREAD, PLUG OR CAP THE END OF THE DRAINLINE.

The boiler needs a large quantity of air for combustion, the specified vent must be installed. Incomplete combustion will occur and prevent normal operation of the boiler.

For safe operation, an ample supply of air must be provided for proper combustion and ventilation in accordance with the national fuelgas code or applicable provisions of the local building codes (latest editions). An insufficient supply of air may result in a yellow, luminousburner flame, carboning or sooting of the finned heat exchanger, or create a risk of asphyxiation. Do not obstruct the flow of combustionand ventilation air.

NEVER OPERATE THE HEATER UNLESS IT IS VENTED TO THE OUTDOORS AND HAS ADEQUATE AIRSUPPLY TO AVOID RISKS OF IMPROPER OPERATION, FIRE, EXPLOSION OR ASPHYXIATION.

The boiler should be at least 600mm away from electric appliances. The boiler is set up for AC 220V, 50/60Hz.

The flow of combustion air to the boiler must not be obstructed.

The boiler area must be kept clear and free from combustible materials, gasoline and other flammable vapors andliquids.

Flue made of stainless steel.

To facilitate the discharge of exhaust gas, the flueshould be installed with fewest possible bents andcurves. The flue should have a diameter larger than that of the flue of the boiler. Do not place flammable item near the boiler.

Never place combustibles such as vinyl bags,match, thinner, etc on boiler.

Read first before connection to power supplyLow Voltage(Thermostat Wire)

Orange Orange

BlkRed

Black

WhiteGreen

Low Voltage(for optional gas alarm)

Gray Wire(to live voltage)

More than 600mmOnly for AC220V, 50Hz

KDB-GOM Series

- 38 -

2. Identifying the components of the boiler

Model : KDB – 251 / 301GOM

Model : KDB – 161 / 201GOM

KDB-GOM Series

- 39 -

3. Installation of water piping

The piping materials used should meet local codes and industry standards.

Piping must be cleaned and flushed-out before installation.

Do not apply torch heat within 300mm of the bottom connections of the unit.

Perform all solder connections at a safe distance from the (brass) male

connectors below the unit. Allow fittings to cool, before attaching to unit. Use only approved coupling unions with

O-rings to attach field piping to unit.

The ‘heating’ pipe should be 3/4" and of type-L copper. Never use aluminum, plastic, or galvanized steel piping.

The pipe size used for supply heating water should be the same size used for the return heating water.

Use only copper piping with lead-free solder for the domestic water side.

Since the expansion tank has already been installed in the unit, no separate tank is required.

The size of the domestic hot water pipe should be 1/2" diameter.

The length of piping should be as short as possible and the piping should have minimal number of bends and

connections.

Use only ball type isolating valves. Do not use gate valves.

Never leave the heating pipes disconnected while operating the unit as a boiler. This will cause damage to the

heat exchanger and void the manufacturers warranty.

All piping should be insulated.

After making the piping connections, check for gas or water leaks.

If the water supply pressure is 10 kgf/cm² or higher, install the reduction valve on the water supply piping.

If the water supply pressure is 0.3 kgf/cm² or lower, install a pressurizing pump.

KDB-GOM Series

- 40 -

A THERMOSTATIC MIXING VALVE MUST BE ADDED TO THIS SYSTEM TO PREVENT SCALDING. IF YOUCANNOT FIND A MIXING VALVE LOCALLY, PLEASE CONTACT YOUR QUIETSIDE DEALER OR LOCALSPECIALITY PLUMBING SUPPLIER.

Mixing type valve:- Controls the desired hot water temperature and ensures constant hot water temperature in the faucets- Ensures safety through the built-in anti-burn/scald safeguard. Limits the deposits and accumulation of scale.- Includes built-in wire mesh filters and check valves for long and trouble-free operation.

Fig. Schematic of piping installation

There is a risk in using fuel burning appliances in rooms or areas where gasoline, other flammable liquids or enginedriven equipment or vehicles are stored, operated or repaired. Flammable vapors are heavy and travel along the floorand may be ignited by the igniter or main burner flames causing fire or explosion. Some local codes permit operation ofgas appliances if installed 5.0M or more above the floor. This may reduce the risk if location in such an area cannot beavoided. Flammable items, pressurized containers or any other potential fire hazardous articles must never be placed on oradjacent to the boiler. Open containers of flammable material should not be stored or used in the same room with the boiler.

DO NOT INSTALL THIS BOILER DIRECTLY ON A CARPETED FLOOR. A FIRE HAZARD MAY RESULT. INSTEADTHE BOILER MUST BE PLACED ON A METAL OR WOOD PANEL EXTENDING BEYOND THE FULL WIDTH ANDDEPTH BY AT LEAST 75mm IN ANY DIRECTION. IF THE HEATER IS INSTALLED IN A CARPETED ALCOVE ORCLOSET, THE ENTIRE FLOOR SHOULD BE COVERED BY THE PANEL.

99 F50113

104

ROOM TEMP.

140 FOFF MAX

122

68

131 86

77

KDB-GOM Series

- 41 -

4. Installation of the flue

4.1 PVC Venting Method The KDB-GOM Series boiler may be vented using 75mm schedule-40 venting materials.

Cut all lengths of pipe cleanly maintaining a 90-degree square edge. Use long radius elbows whenever possible.

Use only the type of adhesive recommended by the stainless pipe manufacturer.

Keep an uphill slant from boiler to the outside to ensure that all condensed water inside the pipe will return back tothe boiler.

Do not place the outdoor termination kit in an area where discharge gasses will be directed towards evergreenshrubbery.

Assemble the flue using the following illustration as a guide. Your installation may vary slightly from the illustrationshown below.

Use the optional Vent Termination Kit for venting the KDB-GOM boiler to outside area.Use the optional Vent Termination Kit for venting the KDB-GOM boiler to outside area.Use the optional Vent Termination Kit for venting the KDB-GOM boiler to outside area.Use the optional Vent Termination Kit for venting the KDB-GOM boiler to outside area.

- Standard : The Stainless Steel Concentric Flue Kit for KDB-GOM models.

“A” : 75××××1.0m LENGTH STAINLESS FLUE PIPE“B” : 75××××0.5m LENGTH STAINLESS FLUE PIPE“C” : 75××××90-DEG. STAINLESS ELBOW

Shown : 75 (3″″″″) Stainless Venting.

“C”“A” or “B”(Maximum Allowable Flue Length = 5 m)

Min. 250 (10″)

Vent Termination Kit

ExhaustIntake Air

Min. 600 (2 ft) from ground(Note! - Install the vent termination kit in anarea away from plants, people andanimals)φ75 (3″″″″)

Type 304stainless steel

only

NOTE ⅰ) Intake Air : φ75 (3″″″″) stainless steel. ⅱ) Exhaust : φ75 (3″″″″) Stainless steel. ⅲ) Maximum three 90° elbows. ⅳ) Slant flue pipe 2-3° away from boiler to outside, to drain condensate.

Ground

KDB-GOMBOILER

“C”To Drain

Install Horizontal DripTee

If Required

KDB-GOM Series

- 42 -

4.2 Flue pipes used for STS exhaust flue kit When the flue duct (including extension) passes through a combustible wall or ceiling with combustible materials,

it should be insulated with 25mm or thicker insulation and then set apart from the wall or materials by 50mm ormore. When it passes through the ceiling, include an opening for inspection of the flue.

If the air supply duct is separated from the flue duct, the total length of the flue duct should be 3.0 M or less andwith 2 or less elbows.

The connection of the air supply hose must be sealed by the wire clamp to prevent any air loss. In the connectionof the flue duct and the flue elbow, In O-ring must be inserted to prevent leakage.

Do not use any aluminum duct as an extension. Use extension duct sets or elbows available through yourkyungdong distributor.

The flue duct which carries combustion waste gas should be firmly secured by the clamp so that it will not loosendue to vibration. The parts where the band clamp is not used should be sealed with aluminum tape.

In the event the exhaust pipe passes through a combustible wall or an combustible ceiling, insulate it withnonflammable materials of 25mm thick or more and locate 50mm or more away from any combustible materials.

In addition, install a check port if flue passes through the ceiling.

Tie up a joint of the air intake hose with the wire clamp so as not produce a loss of an intake air, insert an O-ring in ajoint of the exhaust pipe and exhaust elbow so that the exhaust gas won’t leak.

Fix the exhaust pipe with the band clamp and screws so as not to pull due to shock. Make sure to wrap any pipe jointnot using a band clamp with aluminum tape.

Fig. Schematic of Standard Flue kit Installation

Ceiling

Seal opening to ensure that burnedwaste gas does not enter the room.

In the event the intake hose is toolong, cut the shortest length aspossible and connect it.

Nonflammablewall

150 or more

250ormore

500 ormore

Install the horizontal part of flue downwards(120mm)so that the condensed water from the flue or rain doesn’t enterinto the boiler.

Install the flue in a place where there are no any obstacleswithin 1.5M away from the flue.

Install the flue ensuring no that it cannot be blocked by snowfalling from the roof eaves.

Install the flue in a place in a location opening exist within 500 mmfrom the flue so that exhaust gas can’t re circulator in to the building.

Install the flue at least 600mm above the ground.Unit : mm

KDB-GOM Series

- 43 -

5. Gas piping connections

The heating water supply piping should be 3/4". An isolation (ball-type) valve should be installed before the piping isconnected to the units.

Black iron piping or 3/4" flexible connector (approved by the local authorities for gas) should be used for gas piping. Do not use Teflon tape for gas pipe connections. Install a gas drip leg at the unit. Gas piping should be kept at the required distance away from any electric lines and the main service panel(check

with local authorities).Items Distance (mm)

1. Distance from electric lines 1502. Distance from electric heaters and electric panels 6003. Distance from flue pipes and outlets 300

Install the ball valve(cut-off valve) before connecting the gas piping to the unit (Allow space for the lever’s fullmovement, install valve as close to the units as possible).

After the gas pipe has been completed, all connections must be checked with soapy water. Note! - Do not test forgas leaks by pumping air-pressure into the line without first disconnecting the gas line to the unit. Pressuring theunit will void the manufacturers warranty. Releasing this pressure into the unit will cause immediate and severedamage to the gas valve and its internal pressure regulating device and could result in property damage and/orpersonal injury.

6. Installation of the room thermostat6.1 Choosing the Best Location Never locate the thermostat near or above a heat producing source(lamp, TV, fireplace, radiator, direct sunlight,

etc.).

Never locate in areas with drafts(stairwells, vestibules, foyers, against an outside/exterior wall, etc.).

Never locate in a room, which will be shut-off from the other living areas of the home.

On multi-story homes, locate thermostat on the ground floor.

Install at a height of about 1.2M to 1.5M above the floor.

Keep out of reach from children.

6.2 Installation

1. Remove the back plate from the FR-5 thermostat by grasping the faceplate with one hand and sliding the back platedownward with the other hand.

2. Pull the thermostat wire through the back plate.

3. Connect 2(orange colored/stranded) wires from unit to the 2 screws located on the FR-5 thermostat.

Consult with your gas provider to determine the proper diameter of gas pipe. This will vary due toinput capacity, the number of elbows and length of pipe.

[On Hollow Plaster or Drywall] [On Recessed Outlet]

KDB-GOM Series

- 44 -

4. Mount the back plate to the wall using either of the above techniques(depending on the construction of the wall).Recheck all connections both inside the unit and at the thermostat. Be careful not to pinch the control wires. Pinchedor shorted wires will prevent the system from operating. Do not over tighten wire nut connecting wires together.

5. Use countersunk type screws.

CAREFULLY TIGHTEN THE 2 SCREWS WHEN CONNECTING THE WIRES. DO NOT APPLY EXCESSIVEFORCE.IF THE INSULATION OF THE WIRES IS DAMAGED OR IF THE TERMINALS ARE ON POOR CONTACT, THEROOM THERMOSTAT WILL NOT WORK PROPERLY. BE CAREFUL TO PROTECT THE INSULATION OF THEWIRES.

[Wiring FR-5 Thermostat]

DC 20V

FR-5 Thermostat

2 Orange Wires

MainController

AC 220V, 50/60HzGrounded Power Supplyto Boiler

Boiler

KDB-GOM Series

- 45 -

1. Checkup after installation

2. Checking for gas and water leaks

3. Checks before trial operation

4. Trial operation4.1 Trial operation quick-fill4.2 Procedure of trial operation

5. Routine maintenance

6. Troubleshooting6.1 Troubleshooting - Error Codes6.2 Troubleshooting - Occurs

III. Trial operation & Checkup

KDB-GOM Series

- 46 -

1. Checkup after installation1) Check the flammability and rigidity of floor & wall materials. Ensure that all-minimum clearances to walls, ceilings,

overhangs, etc. have been met.

2) Freeze Prevention Device The units must be wired-in to AC 220 volt electrical circuit once they have been connected to water piping and the

circuit has been filled with water. If the freeze prevention circuit starts due to a low-water condition, the pump willbegin running on “air” and cause premature failure and will void the warranty on the pump.

Check to see if the unit is properly connected and the piping is insulated properly.

If the insulation has worn off or is not fitted, the risk of freezing of piping and severe damage to the unit isconsiderable. Thoroughly check the piping insulation and replace where necessary.

Measures to prevent fire must be taken and check that flue ducts are installed in compliance with the instructions?

2. Checking for gas and water leaks Are there any water leaks in the heating and domestic hot water piping? Are there any gas leaks in the gas piping?

3. Checks before trial operation Type of gas being supplied(the one indicated on the rating plate of the units)

When the type of gas does not match the one specified on the unit rating plate, modification and re-adjusting willbe required(Consult your heating dealer or a qualified technician with the gas utility company).

Test for leakage at all gas piping connections.

Inspect for proper operation of gas alarm system.

AC 220 volts 15 Amp. dedicated circuit with approved grounded connection.

Heating and hot water pipes must be properly installed and in compliance with the standard installation methodsand local code requirements. CAUTION! : Any air remaining in the heat exchanger piping will cause rapid corrosionin the unit.

Completely vent the air at this time.

Check DIP switch setting against the factory settings shown on the control board diagram.

Connect room thermostat and check all wiring connections at control, at molex connectors in unit and at maincircuit panel.

KDB-GOM Series

- 47 -

4. Trial operation4.1 Trial operation quick-fill

STEP 1 Fill water by means of auto water filling system.

STEP 2 DIP switch setting #1 to on.

STEP 3 Run the pump for 2hours.

STEP 4 After trial operation, manipulate DIP switches in the stand-by condition to the stop the trial operation and re-set the switches.

STEP 5 The low water level will be automatically deactivated at 1-minute intervals.

STEP 6 If the flow switch is “ON”, stop the pump and check for any errors.

STEP 7 If DIP switches are set for trial operation, the power lamp will flicker : 1-second “ON” and 1-second “OFF”.

After the installation, connect the unit to an AC 220V, 50/60Hz outlet with the intermediate valve in the watersupply line open and turn the water heater “ON”. The auto water fill will start.

When the temperature sensor terminal is disconnected, the fans and pumps are continuously run to purge air inthe piping.

4.2 Procedure of trial operation

STEP 1 Open the water valve & fill the system.

STEP 2 Fill the units with water by means of the automatic water filling system and wait until the pressure in theheating pipe reaches the maximum pressure(max. pressure through water filling valve). (Air in the heatingwater pipe will cause quick corrosion in the unit. Take the time to completely remove air before proceeding tothe next step.

STEP 3 Wait until the water fill is completed.

STEP 4 Check the unit and turn the unit to “ON” at the room thermostat.

STEP 5 If the CHECK lamp is illuminated, note the error code and follow the steps required according to thetroubleshooting guide. After the corrections or adjustments have been made, restart the unit. Disconnectingand reconnecting the power may be required to restart the unit.

STEP 6 In case of water pipe leaks, turn off power to unit. Shut off all isolation valves. Inspect O-ring connections andreplace if necessary. Check to be sure all fastening clips are securely in place before opening the isolationvalves.

Turn the boiler to “POWER” at the room thermostat.

If the CHECK lamp is illuminated, note the error code and follow the troubleshooting guide. After the require oradjustments have been made, restart the unit. Disconnecting and reconnecting the power may be required torestart the boiler(at power button “POWER”).

In case of leaks water pipes, turn off power to unit. Shut off all isolation valves. Inspect O-ring connections andreplace if necessary. Check all fastening clips are securely in place before opening the isolation valves.

KDB-GOM Series

- 48 -

No. Checking Items Measures

1 Prior to inspection and maintenance. Close the gas shut-off valve, or turn off power to theunit.

2 Check for leaks in gas piping & connectionswith soapy water. Repair the leak.

3 Emergency measures for a gas leak.

1) Close the gas shut – off valve.2) Prohibit the use of any device which may cause gas

to ignite or explode such as matches, lighters, or

turning switches on or off.

3) Ventilate the indoor space.4) Contact the gas supplier or call the fire department

or 911.

4 Check for obstructions in air intake andexhaust (flue) pipe.

Stop the unit and immediately contact the installer orservice company.

5Check for lack of heating water.(Low volume or flow of water supplied to tubor faucets)

Check the pressure of the incoming water supply (Ifthe pressure is lower than the minimum hot waterpressure, install a separate pressurizing pump).

6 Check for external contamination. Stop the unit and clean with neutral detergent.

7 Precautions for restart after prolonged shutdown.(Typical for vacation homes)

Check if condensate trap is filled to mark. If add waterfill to mark.

8 Check for clogging of the strainers at theheating inlet or hot water inlet.

Clean strainer(s). If clogged it may be ‘advisable to’flush system completely

9 Abnormal noise during the operation. Stop the unit and contact your dealer.

10 Drainage of condensed water.(KDB-KC model only)

Siphon should always be filled with water to the top ofthe container. The condensed water drainage shouldbe connected to the sewer. Never drain to areasprone to freezing temperatures. Siphon should becleaned annually.

5. Routine maintenance

KDB-GOM Series

- 49 -

6. Troubleshooting6.1 Troubleshooting - Error Codes

Error Code Cause Troubleshooting

01 / Overheat Clogged / Reduce flow in heating system Circulating pump failure

Check strainer clean Check system for air rate Check pump for operation –220V AC = 1 Amp

02 / Low Water Level

No water in system / Pump failure No make up water supply Water fill valve failure

Check system / Check pump Check system Check system 5V DC- input signal

03 / Ignition Failure

Check ignition transformer Check high limit switch / fuse No gas supply

Air pressure switch tripped

Input 220V AC N/C contacts Check gas connection Check gas valve Check tube for connection Check flue for blockage

04 / Flame Sensor

Low gas pressure

Fan failure / Airflow pressure switch

Check gas valve 220V AC Check gas pressure Check fan for operation Check switch, flue for obstruction

05 / Heating Sensor Wire Disconnected Check molex connection Re - connect

06 / Heating Sensor Short Circuit

Sensor failure Check voltage Pin #15&5 on 21Pin connector,main controller 5V DC

07 / Hot Water Sensor Wire Disconnected Check molex connection Re - connect

08 / Hot Water Sensor Short Circuit

Sensor failure Check voltage Pin #19&8 on 21Pin connector,main controller 5V DC

09 / Fan RPM Failure Fan failure Check speed control

Check fan for operation. Input voltage 7 – 40VDC. Red-Black wires

10 / Air Pressure Switch Failure

Fan failure Air flow switch failure

Blocked flue Excessive wind gusts

Check fan for operation Check tube connection Check voltage 5V DC Check flue for blockage Check flue termination - relocate

11 / Water level Detection Failure Check water fill valve Voltage 5V DC

12 / Flame Failure

Low gas pressure

Fan failure / Air flow sensor

Blocked flue

Check gas pressure Check gas valve Check fan for operation Check tube on air flow sensor Check air flow sensor – 5V DC Check flue for obstruction

13 / Heating Water Switch Failure

Faulty switch Check voltage – 5V DC on Pin #10 on 13 pin andPin #17 on 21 pin connectors

14 / Gas Alarm (Optional)

Check if connected (Red / Black wire) Re – connect Check gas supply Check voltage 5 – 20V DC

15 / MICOM Failure Check connection from t-stat to unit Replace t-stat or micom controller

16 / Mechanical Overheat

Pump motor overheat

Fan motor overheat

Check for pump operation 220V AC, approx 1A(dependent on flow rate) Check fan for operation Check rotation

17 / DIP Switch Setting Incorrect settings Check setting especially

KDB-GOM Series

- 50 -

6.2 Troubleshooting - Occurs

IF ANY FAILURE OCCURS, CHECK THE FOLLOWINGS BEFORE CONTACTING A SERVICE OR A DEALER. IF THE CHECK LAMP COMES “ON” AND THE FAILURE CODE IS DISPLAYED, TAKE PROPER ACTIONS AND THEN

RESTART THE UNIT. (RE-PLUG IN THE UNIT OR TURN THE UNIT “ON” FEW MINUTES AFTER THE CHECK LAMP HAS COME

“ON”) IF SUCH PROCEDURE DOES NOT WORK, CONTACT THE NEAREST SERVICE CENTER. CERTAIN NON HAZARDOUS FAILURES WILL SHUT DOWN THE UNIT, BUT WILL NOT ILLUMINATE CHECK

LIGHT. PRESS ON/OFF BUTTON TO OBTAIN ERROR CODE.

Symptoms Causes Troubleshooting

Blown fuse Replace new fuse

Power failure Wait until the power restores No indication onthe water temperatureindicator

Repair the plug Room temperature is higher than theset temperature

Increase the set temperature at the room thermostat

Set temperature at the unit thermostat is low

Increase the set temperature at the thermostat

Temperature isindicated but the unitdoes not work

“02” is indicated onthe temperatureindicator

No water in the heating pipe Water filling valve failure No tap water supply

Fill the heating water Contact the service center

The unit doesnot work

“01” is indicated onthe temperature indicator

Clogged heating pipe Circulation pump failure

Check for any clogging in the heating pipe. If the pipe is clogged, contact the unit installer Clean the heating strainer Check the circulation pump※ After removing the cause, press the“POWER” button again

Low or no gas pressure Contact for service No flame detection Contact for service Intermediate valve closed Open the valve

When the unit is started, the ignition fails and the check lamp comes“ON”

No ignition Contact for service Air pressure switch tubedisconnected Connect the tube

Incorrect installation of flue Correct the wrong installation Ignition fails and the exhaust fan runs continuously

Clogged flue exhaust pipe Check the smoke stack Closed valve on the heating line or clogged pipe(Heating water) Check the heating pipe(strainer)

Air in the heating pipe Purge the air from the piping

Circulation pump does not work Contact for service

The unit runs properly but heat performance id poor

Leak in heating pipe Fix the leak Low water pressure Install a pressurizing pump Circulation pump does not work Contact for service The unit runs normally but hot water is

not supplied Defective 3-way valve Contact for service

Pressure falls Leakage in piping Contact for service installation of flue duct Contact for service Loud noise during the ignition and

combustion Clogged flue pipe(s) Contact for service

Clogged hot water line Clean the strainer at the inlet of the hot water flow switch Hot water supply stops

Defective hot water flow switch Contact for service

KDB-GOM Series

- 51 -

1. Conversion Kit Contents

2. Parts & Tools Required

3. Conversion Procedure

IV. Fuel Conversion Method

KDB-GOM Series

- 52 -

MODEL : KDB – 161 / 201 / 251 / 301GOM – LNG , LPG

KyungDong, GOM SeriesKyungDong, GOM SeriesKyungDong, GOM SeriesKyungDong, GOM Series

Gas ConversionGas ConversionGas ConversionGas Conversion

Installation ManualInstallation ManualInstallation ManualInstallation Manual

1. Conversion Kit Contents

2. Required Parts & Tools

- Conversion Kit : Correct Kit for Model # and Capacity. Refer to Table 1.- Tool : Screwdriver- Gauge : Gas Pressure Gauge(eg: manometer)

This conversion kit is to be installed by a qualified installer/service technician in accordance with theKyungDong Boiler instructions and all local code requirements.

Failure to follow all instructions in proper order can cause severe personal injury or death. The qualified technician performing this work assumes responsibility for this conversion.

DO NOT TAMPER WITH NOZZLE SIZE. CHANGING OR MODIFYING IN ANY WAY CANCAUSE SEVERE PERSONAL INJURY OR DEATH.

-110*10*3t,1EA

Nozzle Holder Packing-100*10*3t,1EA

:for Nozzle Holder

-17.5*2.7t,1EA:for Gas Valve

:for Burner Cover(Only 120/140W1)

-324*10*2t,1EA-305*10*2t,1EA

-130*10*2t,2EACeramic Packing

Manual

O-Ring

:for Nozzle HolderNozzle Holder

:for Nozzle Holder,Gas Valve

Gas ConversionInfo. Sticker

(Only 075/095W1)(Only 120/140W1)

-M4*12L,2EA

Bolt-4*12L,2EA

KDB-GOM Series

- 53 -

Shut off the gas supply & power.

Change Nozzle Assembly.

[Table 1] Instructions apply to the following conversion kits:

Natural Gas Propane Gas

Boiler Model Conversion Kit, # Nozzle Size ()

KDB – 161GOM, L NG 161GOM LPKT Ø 0.92

KDB – 201GOM, LNG 201GOM LPKT Ø 1.06

KDB – 251GOM, LNG 251GOM LPKT Ø 0.95

KDB – 301GOM, LNG 301GOM LPKT Ø 1.06

Refer to the following instructions,To convent the boiler fuel type.

STEP 1.STEP 1.STEP 1.STEP 1.

STEP 2.STEP 2.STEP 2.STEP 2.

3. Conversion Procedure

2.1 KDB – 161 / 201 GOM1) Remove 11 screws holding front cover to heat exchanger. Disconnect thermal fuse.

Do not forget 2 screws on top of heat exchanger.2) Remove front cover, be careful with sealing gasket.3) Remove bracket holding igniter transformer to gas nozzle assembly.

Disconnect igniter wires and ignition sensor.4) Remove 4 screws holding nozzle assembly. Remove nozzle assembly from unit.5) Replace nozzle assembly with new assembly from L.P kit. Do not forget to install new O-ring.6) Replace 4 screws:

Tip : Install assembly into gas valve first, and install screw on RHS of assembly first.7) Replace front cover and thermal fuse mount. Reconnect fuse.

Seal front cover with high temp. silicone seal ( not supplied ). 8) Replace igniter transformer bracket and reconnect igniter and sensor.

2.2 KDB – 251 / 301 GOM1) Remove igniter wires and ignition sensor wire. Remove ignition transformer, disconnect wires at molex plug.2) Remove 12 screws holding front plate to the combustion chamber.3) Remove front plate from the combustion chamber, be careful with the sealing gasket.4) Remove 4 screws holding the nozzle assembly. Remove nozzle assembly from the unit.5) Replace nozzle assembly with new assembly provided in the L.P kit. Do not forget to install the O-ring.6) Install assembly in gas valve first then secure with screw in assembly RHS first.7) Replace cover, be careful not to strip screws. Use a high temp. silicone sealant to seal cover (not supplied).8) Replace igniter transformer, igniter wires and ignition sensor wire.

KDB-GOM Series

- 54 -

Switch DIP switch #5 (“B”) on the main controller to the new settings Table 2. L.P. Gas : DIP switch # 5 "ON"

Natural Gas : DIP switch # 5 "OFF"

[Fig. 1] Procedure of gas conversion

[Table 2] DIP switch setting on the main controller

[Table 3] Gas modulating valve head(H2O)

No ON OFF

1 Trial operation Normal2 Forced Max. Combustion Normal3 Forced Min. Combustion Normal4 F.E F.F5 L.P Gas Natural Gas6 Sealed combustion Open Combustion7 50 Hz 60 Hz

Gas Modulating head Pressure , mmH₂₂₂₂O(inch W.C.)

Max. Load Min. Load

Front PanelON

Front PanelOFF

Front PanelON

Front PanelOFF

KDB-161GOM-NG Natural Gas 100 (3.94) 104 (4.10) 16 (0.63) 18 (0.71) φ1.33 (0.052)

161GOM-LP L.P. Gas 170 (6.70) 174 (6.86) 26 (1.02) 28 (1.10) φ0.92 (0.036)

KDB-201GOM-NG Natural Gas 104 (4.10) 108 (4.26) 16 (0.63) 18 (0.71) φ1.46 (0.057)

201GOM-LP L.P. Gas 150 (5.91) 154 (6.07) 26 (1.02) 28 (1.10) φ1.06 (0.041)

KDB-251GOM-NG Natural Gas 104 (4.10) 110 (4.34) 20 (0.79) 22 (0.87) φ1.37 (0.053)

251GOM-LP L.P. Gas 164 (6.46) 170 (6.70) 24 (0.95) 26 (1.02) φ0.95 (0.037)

KDB-301GOM-NG Natural Gas 106 (4.18) 116 (4.57) 20 (0.79) 22 (0.87) φ1.50 (0.059)

301GOM-LP L.P. Gas 156 (6.15) 166 (6.54) 28 (1.10) 30 (1.18) φ1.06 (0.041)

- Key - ①Igniter wire & Ignition sensor ③Ignition Transformer ②Combustion chamber ④Nozzle Assembly

STEP 3.STEP 3.STEP 3.STEP 3.

KDB-GOM Series

- 55 -

Set offset of the gas control valve.

1) Shut off the power.2) Switch DIP switch #3 on the main controller to ON, It will make the unit run at Min. load (forced Min. combustion

mode).3) Connect the gas pressure gauge hose to the gas pressure check nipple ("C").4) Restore the power and supply gas. Caution! Check any gas leak with soapy water. If error code #17 is displayed on the panel of the room controller, check on DIP switch #3 setting.5) Close all the water inlet valves. Then, set the Min. load gas pressure Refer to Table 3.

Turn the adjusting screw("D") counterclockwise and ΔP will go up, turn clockwise ΔP will go down.

※ Check for abnormal combustion noise if this occurs: Check STEP 4. gas leak and close the water inlet valve again.

Check STEP 2. nozzle holder assembly fitness.※ Check for abnormal burning noise if this occurs: Check STEP 4. gas leak and close the water inlet valve again. Check STEP 2. nozzle holder assembly fitness.

6) After procedure is complete shut off power supply.7) Set the DIP switch #3 to off, back to normal.8) Set DIP switch #2 on, it will make the unit run at Max. load (forced Max. combustion mode).9) Restore the power again and supply the gas. If error code #17 is displayed on the panel of the room controller, check DIP switch #3 setting.10) Close all the water inlet valves. Then, set the Max. load gas pressure refer to Table 3. Turn the adjusting screw("A") clockwise and ΔP will go up, turn counterclockwise ΔP will go down.

※ Check for abnormal combustion noise if this occurs: Check STEP 4. gas leak and close the water inlet valve again.

Check STEP 2. nozzle holder assembly fitness.※ Check for abnormal burning noise if this occurs: Check STEP 4. gas leak and close the water inlet valve again. Check STEP 2. nozzle holder assembly fitness.

11) After procedure is complete shut off power supply.12) Set the DIP switch #2 off, back to normal operation mode.

Final check.Supply power to run the boiler, and check for any abnormal noise or check lamp on the room controller.When the check lamp is on and an error code is displayed on the room controller panel, Refer to servicemanual.

STEP 4.STEP 4.STEP 4.STEP 4.

CAUTIONCAUTIONCAUTIONCAUTION:::: If an abnormal combustion or burning noise isheard, Check the nozzle holder assembly is correct one for theboiler & gas and try STEP 4STEP 4STEP 4STEP 4 again

STEP 5.STEP 5.STEP 5.STEP 5.

KDB-GOM Series

- 56 -

1. Failure code #02, Low Water Level

2. Failure code #03, Ignition Failure

3. Failure code #04, Pseudo Flame

4. Failure code #05, Disconnection of the heating sensor

5. Failure code #06, Short circuit of the heating sensor

6. Failure code #09, Abnormal RPM

7. Failure code #10, Air Pressure Failure

8. Failure code #12, Flame Failure in Combustion

9. Failure code #13, Heating Flow Sensor Failure

10. Failure code #14, Gas Alarm (Optional)

11. Failure code #15, MICOM Failure

12. Failure code #16, Mechanical Overheat

13. Failure code #17, DIP Switch Setting Error

14. Others – 1, 2, 3, 4 and 5

V. Troubleshooting

KDB-GOM Series

- 57 -

1 # 02 Failure Low water level

No Symptoms and Causes Solutions Reference

The heating flow sensor has to be ON within3 seconds after the power supply. If it is stillOFF after 3 seconds, the failure code # 02will be displayed.

1) Heating valve (Splitter) is closed. - Open the splitter valve <Fig. 1>

2) Heating water is lacking. - Adjust the heating pressure gauge between0.5~1.5kgf/cm2 (49 ~147 kPa)

<Fig. 2>

3) Too much air in the heating line. - Remove air from the heating line.

4) The circulation pump is working but thereis not enough RPM or the impeller isdamaged.

- Check the resistance of the circulation pumpcoils terminal. 0 level is normal. If it showsinfinite level the coil is short-circuited and thecirculation pump has to be replaced.

<Fig. 3>

1

5) There is no point of contact in the heatingflow sensor.(close model)

- When the boiler is running and the heating flowsensor point of contact is normal, theresistance should be 0. if it shows an infinitelevel it is defective and has to be replaced.

- Reconnect the boiler earth wire.

<Fig. 4>

Check valve is open

Splitter valve

<Fig. 1> <Fig. 4>

Circulation pump

<Fig. 3>

Heating flow sensor

kgf/(kPa)

0.5(49)

1.5(147)

Heating Pressure gauge

<Fig. 2>

Measureresistance

KDB-GOM Series

- 58 -

2 - 1 # 03 Failure Ignition failure

No Symptoms and Causes Solutions Reference

Failure code # 03 indicates ignition failureof the combustion device

In case there is no combustion and failurecode # 03 is displayed

1) Gas supply is not normal. [Supply pressure standard] - LNG : 200 50

100+− mmH2O

- LPG : 280±50 mmH2O

- Check supply pressure and call the gascompany if not normal.

<Fig. 1>

- Check power supply from the controller to theignition transformer.

- If there is no power supply, replace the maincontroller.

<Fig. 2>

- If there is power supply but the ignitiontransformer is not working properly, check forcoil short circuit. If the resistance shows aninfinite level, it is defective and needs to bereplaced.

<Fig. 2>

2) Ignition transformer is not working.

- The secondary voltage should be 19.5kV and ifit comes out weak, the ignition transformer hasto be replaced.

1

3) Space between electrodes anddischarge.

- Check whether crevice between electrodes is2~3mm and adjust accordingly.

- Check whether the electrodes are not banded ina direction.

<Fig. 3>

<Fig. 1> <Fig. 2> <Fig. 3>

Gas InletConnection

Supply PressureMeasure Hole

Blue

Main Controller

IgnitionTransformer

ElectrodeAssembly

Electrode Crevice2~3 mm

KDB-GOM Series

- 59 -

그림그림그림그림4

2 - 2 # 03 Failure Ignition failure

No Symptoms and causes Solutions Reference

- Check for a crack in the electrode insulator andreplace the electrode if found.

<Fig. 1>

- Check whether the high limit fuse is shortcircuited through resistance measurement. If itshows an infinite level, it is defective andneeds to be replaced.

<Fig. 2>

4) No power supply to the modulating gascontrol valve.

- Check for power supply (AC 220V) from thetransformer to the modulating gas controlvalve. If there is no power supply, replace thetransformer.

- If the symptoms remain after performing thecheck up described above, then replace thecontroller.

<Fig. 3>

5) There is power supply to themodulating gas control valve but it isstill not working.

- Check whether the modulating gas controlvalve coil is short-circuited. If the resistancemeasurement shows an infinite level, replacethe modulating gas control valve.

<Fig. 4>

6) There is power supply to themodulating gas control valve and thecoil is not damaged but still there is noignition.

- The internal diaphragm of the gas control valveis defective. Replace the gas control valve.

- Using the water manometer, check the firstand second head pressure (refer to gaspressure chart of GOM technical documents,and adjust the first and second pressure.

<Fig. 4>

<Fig. 1>

<Fig. 4>

ElectrodeAssembly

Insulator damage

<Fig. 2> <Fig. 2>High Limit Fuse

Measure resistance

<Fig. 3>Power Transformer

BLK BLKCheck AC 220V

ModulatingGas Control Valve

Nozzle HolderAssembly

SecondaryPressureMeasuring Hole

KDB-GOM Series

- 60 -

2 - 3 # 03 Failure Ignition failure

No Symptoms and causes Solutions Reference

- Check the connection of the flame sensor onthe electrode.

- Reconnect the flame sensor on the electrode.

- If problem persists, replace electrode assembly.

<Fig. 1> 2 Combustion is working and failure code

# 03 is displayed.

- Check for power supply (AC 200V) from thepower transformer to the flame sensor. If not,replace the power transformer.

※ Voltage Supply Chart

<Fig. 2>

<Fig. 1> <Fig. 2>

Power Transformer

Check AC 200V

Electrode Assembly

Check flame rodWire connection

No Voltage Check Points

3 200V Flame rod

1, 5 20V Controller circuitry

4, 7 12V Water level detection

2, 6 40V Modulating gas controlSolenoid valve

8, 9 220V Modulating gas controlvalve ON/OFF

KDB-GOM Series

- 61 -

3 # 04 Failure Pseudo flame

No Symptoms and causes Solutions Reference

What’s a pseudo flame?

Combustion takes place normally but aflame is detected in the combustion areabefore the modulating gas control valvestarts operating inducing the boiler to stopits operation.

1 The boiler operation is stopped andpower is supplied to the modulating gascontrol valve.

- If power is supplied then the controller isdefective. Replace the controller.

<Fig. 1>

2 There is no power supply but there aresmall flames in the combustion areawhen the boiler stops operation.

- There is a problem with the diaphragm insidethe gas control valve. Replace the gas controlvalve.

- If the symptoms remain after performing thecheck up described above, then the controlleris defective and has to be replaced.

<Fig. 2>

<Fig. 1> <Fig. 2>

Modulating Gas Control Valve

Main Controller

Internal diaphragm

KDB-GOM Series

- 62 -

4 # 05 Failure Disconnection of the heating temp. sensor

No Symptoms and causes Solutions Reference

Failure code # 05 is displayed when theheating sensor is short circuited ordisconnected.

1 Bad connection between the heatingtemp. sensor and the harness connectingthe controller.

- Reconnect the connecting harness terminal. <Fig. 1>

2 The heating temp. sensor is short-circuited therefore unable to detect.

- The heating temp. sensor is defective and hasto be replaced.

- If there is nothing wrong with the above, themain controller is defective and has to bereplaced.

<Fig. 1>

Main Controller

Check connection

Heating TemperatureSensor

KDB-GOM Series

- 63 -

5 # 06 Failure Short circuit of the heating temp. sensor

No Symptoms and causes Solutions Reference

Failure code # 06 is displayed when theheating temp. sensor shows atemperature greater than 120,interpreting it as a short circuit of theheating sensor. A bad heat circulation ora mechanical deficiency may abruptlyincrease the temperature.

1 When the circulation pump does notwork.

- Check for the short circuit of the circulationpump coil. Measure the resistance and if itdisplays infinite level (0 level is normal) the coilis short-circuited and the circulation pump hasto be replaced.

<Fig. 1>

- Check whether the 3-way valve coil is shortcircuited. Measure the resistance and if itdisplays infinite level (“0” level is normal) thecoil is short-circuited and the 3-way valve hasto be replaced. Check whether the ball insidethe 3-way valve has fallen and if it did replacethe 3-way valve.

<Fig. 2>2 In case the ball falls down when the 3-way valve is on the hot water side, the hotwater flow switch will also always be onthe hot water side. Therefore, since theheating water is not circulating, thetemperature goes up abruptly when theboiler starts operation.

- Check the point of contact of the hot water flowswitch when the boiler is idle. If it shows aresistance of infinite level it is normal but if itshows “0” it is defective and the hot water flowswitch has to be replaced.

- If the symptoms remain after performing thecheck up described above, then replace theheating temp. Sensor and the main controller.

<Fig. 3>

<Fig. 1> <Fig. 2> <Fig. 3>

Measureresistance

Circulation Pump

Hot Water Flow Switch

3-Way Valve

Check whether ball has fallen

Measureresistance

Measureresistance

KDB-GOM Series

- 64 -

6 # 09 Failure Abnormal RPM

No Symptoms and Causes Solutions Reference

1 Fan unit RPM is too slow. - Replace the fan unit. <Fig. 1>

2 The fan does not rotate. - Check whether the fan unit coil is short-circuited. Measure the resistance and if itdisplays infinite level (“0” level is normal) thecoil is short-circuited and the fan unit has to bereplaced.

3 The fan RPM check board (phase controlsensor) is out or defective.

- If the phase control sensor is out, reassembleit. If the check board is defective, replace thefan unit.

4 The connection of the connector terminalis defective.

- Reassemble the connector terminal.

- If the symptoms remain after performing theabove, replace the controller.

<Fig. 1>

Phase control sensor

Measureresistance

Fan Assembly

KDB-GOM Series

- 65 -

7 # 10 Failure Air pressure failure

No Symptoms and Causes Solutions Reference

The KDB-GOM boiler air pressure switchalways operates at the ON position ofcontact B and displays failure code # 10in case of back pressure or back fire.

1 The diaphragm inside the air pressureswitch is defective and the contact is OFF.

- Check the resistance of the air pressure switchterminal when the boiler is idle and if it showsan infinite level (“0” is normal), it is defectiveand the air pressure switch has to bereplaced.

<Fig. 1>

2 The installation and the position of the flueis not appropriate.

- Correct the flue due the formation of a windpressure zone.

- Check whether the connector terminal is wellassembled and reconnect.

If the symptoms remain after checking theabove, replace the main controller.

<Fig. 1>

Air Pressure Switch

KDB-GOM Series

- 66 -

8 - 1 # 12 Failure Flame failure in combustion

No Symptoms and Causes Solutions Reference

Flame failure in combustion occurs whenthe flame disappears during combustion10 times consecutively.

- Check gas supply pressure

LNG: 100 ~ 250 mmAq.,

LPG: 230 ~ 330 mmAq

- Check whether LPG is empty when gaspressure is low and if it is replace with a newfull container.

<Fig. 1>

- In cold seasons, the gas container may notsupply gas normally. Warm up the containerfirst.

- LPG hose may be too long (more than 3 m) orhave fold down. Replace the hose or shortenit.

- The gas meter may be defective. Contact thegas company for replacement.

<Fig. 2>

1 Gas supply pressure is not right.

- Gas initial supply pressure of 200 mmAq mayfall down under 100 mmAq after combustion.In that case contact the gas company.

KyungDong

<Fig. 1> <Fig. 2>

L.P. Gas Container

Gas Meter

KDB-GOM Series

- 67 -

8 - 2 # 12 Failure Flame failure in combustion

No Symptoms and Causes Solutions Reference

2 Gas meter capacity is insufficient. - Boiler capacity is 30,000 kcal/h (34.9 kW) and incase the gas meter is third class gas supplymay not be smooth. Contact the gas companyfor replacement. (refer to Chart 2)

<Fig. 1>

3 Flame rod is too close to the burner. - Adjust crevice between Flame rod. <Fig. 2>

- Replace modulating gas control valve

- If symptoms remain after the check up above,replace the controller.

<Fig. 3>

※ Chart 2Gas meter class per usage capacity (unit: kcal/hr)

Boiler capacity Gas range Total Meter class

10,000~25,000 7,500 17,500~32,500 third

30,000~40,000 7,500 37,500~47,500 fifth

4 Modulating gas control valve does notadjust gas volume.

※ gas range 1hole : 2,500 kcal/h

Space between flame sensor2~3mm with the burner

Electrode Assembly

Kyungdong

<Fig. 1> <Fig. 2> <Fig. 3>

Gas Meter

Modulating GasControl Valve

KDB-GOM Series

- 68 -

9 # 13 Failure Heating flow sensor failure

No Symptoms and Causes Solutions Reference

Heating flow sensor failure occurs onlyin close air system boiler.

1 Heating flow sensor is ON although thepump is not operating.

- Measure the resistance of the heating flowsensor. When the circulation pump is notworking resistance should indicate infinity andzero when it is working. If there is no changeaccording to the pump movement, clean theheating flow sensor or replace it.

<Fig. 1>

<Fig. 1>

Heating Flow Sensor

Measureresistance

KDB-GOM Series

- 69 -

10 # 14 Failure Gas alarm

No Symptoms and Causes Solutions Reference

After the installation of the gas alarm(optional feature), gas leak is detected andalarm goes off.

1 There is no gas leak and failure code # 14is displayed.

- Gas alarm is defective and has to bereplaced.

<Fig. 1>

<Fig. 1>

Gas Alarm(Optional)

KDB-GOM Series

- 70 -

11 # 15 Failure MICOM failure

No Symptoms and Causes Solutions Reference

1 MICOM controller failure. - Replace the controller when displayed failurecode # 15.

<Fig. 1>

<Fig. 1>

Main Controller

KDB-GOM Series

- 71 -

12 # 16 Failure Mechanical overheat

No Symptoms and Causes Solutions Reference

When the high limit sensor (98) locatedon the upper right pipe of the main heatexchanger starts operation.

1 The heating valve is shut down and thetemperature abruptly goes up.

- Open the splitter valve if it is closed. <Fig. 1>

2 The hot water sensor in ON and the 3-way valve shuts off the heating side.

- Separate the hot water flow switch jack and ifthe 3-way valve goes back to its initial position,the hot water flow switch is defective and hasto be replaced.

<Fig. 2>

3 The high limit sensor is defective andfailure code # 16 is displayed when theboiler does not operate.

- Replace the high limit sensor.

- If the symptoms remain after checking theabove, replace the main controller.

<Fig. 3>

Terminal separation

<Fig. 1> <Fig. 2> <Fig. 3>

Splitter Valve Hot Water Flow Switch High Limit Sensor

KDB-GOM Series

- 72 -

13 # 17 Failure DIP switch setting error

No Symptoms and Causes Solutions Reference

The DIP switch located on the upper partof the controller has not been setaccording to capacity.

1 Failure code #17 is displayed althoughthe controller DIP switch has been setaccording to capacity.

- The controller is defective and has to bereplaced.

<Fig. 1>

<Fig. 1>

Main Controller

NO 161GOM 201GOM 251GOM 301GOM

8 OFF OFF ON OFF

9 ON ON OFF OFF

10 ON OFF ON ON

NO ON OFF

1 Run Normal

2 Forced maximumCombustion Normal

3 Forced minimumCombustion Normal

4 FE FF

5 L.P. gas Natural gas

6 Close air type Open tank type

7 50 Hz 60 Hz

CheckDIP switch setting

KDB-GOM Series

- 73 -

14 - 1 Others Failure Boiler is operating normally but water overflowstoward the expansion tank

No Symptoms and Causes Solutions Reference

- There are many impurities in the heating waterof the heating pipeline and in the water pipelinethat are stuck on the water filling valve solenoiddiaphragm and water slowly flows in. replaceand clean the solenoid.

<Fig. 1>1 The water fill valve is defective andcannot stop water and heating water.

- Especially, in case the splitter material isaluminum, corrosion is fast and there isformation of much impurities. Replace with asplitter in copper or stainless steel.

<Fig. 2>

2 Water overflows due to an internal sinkingof the hot water heat exchanger.

- If water still overflows after the checking above,it is an internal sinking of the hot water heatexchanger and the hot water heat exchangerhas to be replaced.

Flue EXhaust Combustion Air Inlet

Domestic Water Outlet

Gas Inlet

Tap Water Inlet

<Fig. 1> <Fig. 2>Check hating pipeline condition

Check splitter valve’s material

Water filling valve

Internaldiaphragm

KDB-GOM Series

- 74 -

14 - 2 Others Failure Heating is working but domestic water comesout cold or does not come out at all.

No Symptoms and Causes Solutions Reference

First, set the room thermostat to thedomestic water position and open thedomestic water tap.

1 The operating lamp does not light up. - The operating lamp does not light up becausethe hot water flow switch is defective. Replace it.

<Fig. 1>

2 It is operating but domestic waterdoes not come out.

- Open the domestic water tap and measure theresistance of the hot water flow switch terminal.If it shows “0” it is normal, if it shows infinite it isdefective.

<Fig. 2>

3 The operating lamp is working but theheating pipeline is not warm anddomestic water does not come out.

- Replace the 3-way valve if the heating pipeline iswarm, meaning the transition to heating watersupply mode has not been done due to a failureof the 3-way valve.(check whether the coil isshort circuited and the ball damaged)

- In case there is no heat exchange in thedomestic water heat exchanger, touch the heatexchanger. One side is very hot and the otherside cold. Replace the domestic water heatexchanger.

- If symptoms remain after the checking above, itmay be a problem of hot water supply capacityfrom the boiler. Check it out.

<Fig. 3>

4 In case hot water does not come outduring operation, tap inlet anddomestic water outlet pipes areswitched, and domestic water doesnot come out because hot water flowswitch is not working.

- Check the piping of the switched tap water inletand domestic water outlet.

<Fig. 2> <Fig. 3>

Supply

<Fig. 1>

Room thermostat, FR-5

Operating lamp

Return

Domestic WaterOutlet

Tap WaterInlet

Hot Water Flow Switch

Measureresistance

KDB-GOM Series

- 75 -

14 - 3 Others Failure Domestic water comes out but heating is notworking

No Symptoms and Causes Solutions Reference

1 The splitter valve is shut down. - Open the splitter valve.

2 Too much air inside the boiler and thepipeline.

- Remove the air from the boiler and the pipeline.

3 Hot water is always ON because the 3-way valve is defective.

- Replace the hot water flow switch.

- The 3-way valve is defective and shuts down theheating. Replace the 3-way valve.

<Fig. 1>

4 There are many impurities in the heatingstrainer and there is no heatingcirculation.

- Clean the strainer by removing the clip below theheating strainer.

<Fig. 2>

5 The heating pipeline is obstructed andthe heating water does not circulate.

- Clean the heating pipeline. (contact the manufacturer)

6 Combustion is normal but the watertemperature goes up late and slowly.

- If the secondary gas supply pressure isinsufficient, adjust it according to capacity usingthe water manometer.

- The heating area may be too big for the boilercapacity. Check the area and the capacityvolume.

<Fig. 1> <Fig. 2>

Check contact point

Hot Water Flow SwitchHeating Strainer

KDB-GOM Series

- 76 -

14 - 4 Others Failure Boiler power lamp indicator does not light up

No Symptoms and Causes Solutions Reference

- Test whether 220V electricity comes out fromthe wall outlet.

<Fig. 1>

- Check whether the boiler internal fuse is short-circuited.

<Fig. 2>

1 Boiler power lamp indicator does not lightup.

- Test the fuse resistance. If 0 it is normal, ifinfinite the fuse is short-circuited and has to bereplaced.

2 The boiler power plug is in, hot water isopen, the boiler is operating and hotwater does not come out.

- Check whether the room thermostat wire isshort-circuited.

<Fig. 1> <Fig. 2>

KDB-GOM Series

- 77 -

14 - 5 Others Failure Too much noise

No Symptoms and Causes Solutions Reference

1 Too many ignition noise during ignition. - There is too much gas during the initial ignition.Adjust the primary gas pressure according toregulations.

2 Ignition noise due to delayed ignition. - Space between electrodes is too close or toofar away. Adjust the space (2~3mm) betweenthem.

- Replace the ignition transformer if itdischarges.

<Fig. 1>

3 Noise during combustion. - The flue bends and length may be aboveregulations (3 elbow 5.0m) and in case of aFF flue the airtight chamber may be damagedcausing a flow of waste gas to the suctionarea. Check the flue and replace if needed.

<Fig. 2>

4 Boiling noise. - Boiling noise may occur when the heatingwater temperature goes beyond a certainpoint due to uncleanness of the heating wateror a defect in the welding of the main heatexchanger brazing. Clean the heating waterand replace the main heat exchanger.

<Fig. 3>

<Fig. 1> <Fig. 2> <Fig. 3>

Crevice between electrode2~3 mm

(Scheme of theair intake hose is omitted)

Nail

Band ClampBand Clamp

Screw

KDB-GOM Series

- 78 -

1. Room Thermostat, FR-5

2. Main Controller

3. Modulating Gas Control Valve

4. Fan Assembly

5. Circulation Pump

6. Expansion Tank

7. Air Pressure Switch

8. 3-Way Valve

9. Heating Strainer

10. Ignition Transformer

11. Electrode Assembly

12. High Limit Sensor

13. High Limit Fuse

14. Hot Water Flow Switch

15. Domestic Water Heat Exchanger

16. Main Heat Exchanger

17. Power Transformer

VI. Procedure of disassembly/assembly

KDB-GOM Series

- 79 -

No 1 Part name Room thermostat

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Separate the room thermostat by pulling up from the bracket.③ Take the two screws connected with the thermostat wire off.④ Separate the wire from the room thermostat.

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① Connect the replaced wire to the thermostat by screwing the two screws.② Pull down the thermostat inside the bracket.③ Plug the boiler into the electric outlet.

Caution

1. Don’t force disassembly. 2. After replacement, check the thermostat during boiler operation.

Room thermostat, FR-5

KDB-GOM Series

- 80 -

No 2 Part name Main controller

Replacement steps

Disa

ssem

bly ① unplug the boiler from the electric outlet.

② open the external cover of the boiler.③ separate the harness terminal from the controller.④ take off the two screws fixing the controller to the external base.⑤ separate the controller from the boiler.

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y ① fix the replacement controller to the external base.② screw the two screws fixing the controller to the external base.③ connect the harness terminal to the controller.④ close the external cover of the boiler.⑤ plug the boiler to the electric outlet.

Caution

Check the connection of the harness terminal thoroughly.

④

⑤

KDB-GOM Series

- 81 -

No 3 Part name Modulating gas control valve

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet and open the external cover.② Close the main gas valve installed on the gas supply pipe outside the boiler.③ Loosen the flexible part connected to the gas inlet connection using manual tools (monkey spanner/group joint

plier).④ Separate the four electric inlet wires connected to the gas control valve.⑤ Separate the six wires connected to the gas control valve (4 ON-OFF valve, 2 proportional control valves ).⑥ Separate the gas control valve and the nozzle by unscrewing the two screws connecting them.⑦ Separate the board holding the ignition transformer and the air pressure switch from the nozzle by unscrewing

one screw.⑧ Separate the gas control valve from the boiler.

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① Fix the gas control valve to the external base.② Screw the four screws fixing the gas control valve to the external base.③ Screw the two screws connecting the nozzle and the gas control valve (*check for the existence or

nonexistence of O-ring when connecting).④ Assemble the parts making sure there is no gas leak.⑤ Open the main gas valve.⑥ Connect the six wires of the gas control valve correctly.⑦ Fix the board holding the ignition transformer and the air pressure switch to the nozzle by screwing one screw.⑧ Plug the boiler to the electric outlet.

Caution

1. Check whether the gas pipe connecting O-ring is correctly assembled. 2. Make sure not to switch the color of the connection terminals. 3. Perform a gas leak test using soap foam after assembly.

⑧

⑦

⑥

④

KDB-GOM Series

- 82 -

No 4 Part name Fan assembly

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the external cover.③ Separate the board holding the ignition transformer and the air pressure switch from the nozzle by removing

one screw.④ Separate the hose connecting the fan and the air pressure switch.⑤ Separate the wire and jack of the fan unit power line and the RPM detector line.⑥ Take off the two screws fixing the fan unit.⑦ Separate the fan unit from the boiler.

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① Fix the fan unit to the boiler.② Screw the two screws fixing the fan unit.③ Connect the jack of the fan unit power line and the RPM detector line.④ Assemble the air pressure switch connecting hose.⑤ Fix the board holding the ignition transformer and the air pressure switch to the nozzle by screwing one screw.⑥ Close the external cover.⑦ Plug the boiler to the electric outlet.

Caution

1. Make sure there is no shaking. 2. Check for unnecessary noise. 3. Make sure all the wires, including the phase controller wire, are correctly connected.

⑦

⑥

③

KDB-GOM Series

- 83 -

No 5 Part name Circulation pump

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the front cover.③ Release the heating water inside the boiler by opening the safety valve below the circulator pump.④ Separate the circulator motor power jack.⑤ Separate the circulation inlet hose and the circulator motor by pulling down the clip connecting them.⑥ Take off heating return pipe and heating flow switch.

⑦ Take off the four screws fixing the circulator pump to the front cover(downside).⑧ Separate the circulator pump from the boiler.

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① Fix the circulator pump to the boiler.② Screw the four screws fixing the circulator pump to the front cover.③ Connect the circulation inlet hose and the circulator pump by pulling up the clip connecting them.④ Connect the circulator pump power line jack and check the safety valve is closed.⑤ Connect the heating flow switch and heating return pipe in the pump outlet.

⑥ Plug into the electric outlet and check for water leakage after water replenishment.⑦ Close the front cover.⑧ Plug the boiler into the electric outlet.

Caution

1. Make sure the O-ring is connected correctly. 2. After assembly, check for water leakage. 3. After assembly, make sure there is no noise due to vibrations or other causes.

③

⑤

⑥

KDB-GOM Series

- 84 -

No 6 Part name Expansion tank

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the front cover.③ Release the circulation pipe clip.④ Release the circulation pipe.⑤ Remove the nut for heating water filling pipe.⑥ Release the nut for circulation pipe connecting the expansion tank and the various parts.⑦ Separate the expansion tank by removing the two screws fixing its front cover.

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① Screw the two screws fixing the expansion tank to the front cover.② Tighten the nut for circulation pipe connecting the expansion tank and the various parts.③ Connect the circulation pipe connected to circulation inlet hose and insert the clip.④ Connect the power cord, check for water leak after replenishing water, and if everything is fine, close the front

cover.⑤ Plug the boiler into the electric outlet.

Caution

1. Check for water leak after assembly. 2. Check whether the sensor wire is correctly connected.

④

③

⑤

⑥

⑦

KDB-GOM Series

- 85 -

No 7 Part name Air pressure switch

Replacement steps

Disa

ssem

bly ① Unplug the boiler from the electric outlet.

② Open the front cover.③ Separate the two wires (yellow) connected to the air pressure switch.④ Separate the air pressure switch by removing one screw from the board holding it.⑤ Separate the air pressure switch connecting hose.

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y ① Fix the air pressure switch to the board by screwing one screw.② Connect the two wires to the air pressure switch.③ Assemble the hose connecting the air pressure switch.④ Close the front cover.⑤ Plug the boiler into the electric outlet.

Caution

1. Make sure there is no shaking after assembly. 2. Make sure the connecting jack is correctly assembled.

④

KDB-GOM Series

- 86 -

No 8 Part name 3-way valve

Replacement steps

Disa

ssem

bly ① Unplug the boiler from the electric outlet.

② Open the front cover.③ Release the heating water inside the boiler by unscrewing the safety valve below the circulator pump.④ Separate the 3-way valve wire jack.⑤ Separate the 3-way valve housing and head by removing the 4 screws on the lower part of the 3-way valve.

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① Fix the 3-way valve to the 3-way valve housing.② Fix the 3-way valve head by screwing the 4 screws.③ Connect the 3-way valve wire jack.④ Screw the drain screw below the circulator pump.⑤ Plug the boiler to the electric outlet and after water replenishment, check for water leak.⑥ If everything is fine, close the front cover.⑦ Plug the boiler into the electric outlet.

Caution

1. Make sure there is no water leak after assembly. 2. Check the jack connection.

④

KDB-GOM Series

- 87 -

No 9 Part name Heating strainer

Replacement steps

Disa

ssem

bly ① Unplug the boiler from the electric outlet.

② Open the front cover.③ Release the heating water inside the boiler by unscrewing the drain screw below the circulator pump.④ Separate the strainer by separating the ㄷ shaped lock.⑤ Separate the hot water heat exchanger from the strainer by removing the connecting clip.⑥ Separate the expansion tank from the strainer by removing the connecting connection.

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① Fix the strainer to the boiler.② Fix the hot water heat exchanger by inserting the connecting clip.③ Fix the expansion tank and the strainer by inserting the connecting connection.④ Fix the strainer by screwing the 3 screws under the front cover (check the packing status between the strainer

and return inlet connection).⑤ Fix the strainer and the ㄷ shaped lock.⑥ Screw the drain screw under the circulator pump.⑦ Unplug the power cord and after water replenishment, check for water leak⑧ If everything is fine, close the front cover.⑨ Plug the boiler into the electric outlet.

Caution

Check for water leak after assembly.

KDB-GOM Series

- 88 -

No 10 Part name Ignition transformer

Replacement steps

Disa

ssem

bly ① Unplug the boiler from the electric outlet.

② Open the front cover.③ Separate the two high voltage cables of the ignition transformer connected to the electrode from the electrode.④ Separate the ignition transformer power cord jack.⑤ Separate the ignition transformer by unscrewing the two screws.

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y ① Screw the two screws fixing the ignition transformer.② Connect the ignition transformer power cord jack.③ Connect the ignition transformer’s two high voltage cords to the electrode.④ Close the boiler’s front cover.⑤ Plug the boiler into the electric outlet.

Caution

1. Make sure fixation is done correctly. 2. Check the connection of the connection jack.

⑤

KDB-GOM Series

- 89 -

No 11 Part name Electrode assembly

Replacement steps

Disa

ssem

bly ① Unplug the boiler from the electric outlet.

② Open the front cover.③ Separate the ignition transformer’s two high voltage cords connected to the electrode from the flame sensor

wire.④ Unscrew the two screws fixing the electrode.⑤ Separate the electrode from the boiler

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y ① Fix the electrode to the boiler.② Fix the electrode by screwing the two screws③ Connect the ignition transformer’s two high voltage cords and the flame sensor wire to the electrode.④ Close the front cover of the boiler.⑤ Plug the boiler into the electric outlet.

Caution

1. Check whether the fixation is correctly done and spark production is good. 2. Make sure the connecting jack is correctly connected.

④

⑤

KDB-GOM Series

- 90 -

No 12 Part name High limit sensor

Replacement steps

Disa

ssem

bly ① Unplug the boiler form the electric outlet.

② Open the front cover.③ Separate the overheating prevention device’s two terminals (red).④ Remove the clip fixing the overheating prevention device ( or unscrew the two screws ).⑤ Separate the overheating prevention device.

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y ① Fix the overheating prevention device by inserting the clip (or screw the two screws ).② Connect the overheating prevention device wire.③ Close the front cover.④ Plug the boiler into the electric outlet.

Caution

1. Make sure fixation is done correctly. 2. Make sure the connecting jack is assembled correctly.

⑤

④

KDB-GOM Series

- 91 -

No 13 Part name High limit fuse

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the front cover.③ Separate the high limit fuse wire jack.④ Separate the high limit fuse unit by unscrewing one screw fixing it.

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y ① Fix the high limit fuse unit by screwing one screw fixing it.② Connect the high limit fuse wire jack.③ Plug the power cord into the electric outlet and check its operation.④ If everything is fine, close the front cover.⑤ Plug the boiler power cord into the electric outlet.

Caution

1. Check fixation is done without any shaking. 2. Make sure the connecting jack is assembled correctly.

④

KDB-GOM Series

- 92 -

No 14 Part name Hot water flow switch

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the front cover.③ Close the water pipeline.④ Separate the board holding the ignition transformer and the air pressure switch.⑤ Separate the fan unit.⑥ Separate the pin connecting the hot water sensor and the hot water heat exchanger and the pin connecting the

hot water inlet and the connection.⑦ Separate the hot water sensor.⑧ Separate the water valve by taking out the hot water sensor and removing the connecting pin from the water

valve.

Asse

mbl

y

① Fix the water valve to the hot water sensor and insert the connecting pin.② Insert the connecting pin into the hot water sensor.③ Fix the fan unit.④ Fix the board holding the ignition transformer and the air pressure switch.⑤ Open the water and check for water leak.⑥ Plugs the power cords into the outlet check the operation. if everything is fine, close the front cover.⑦ Plug the boiler into the outlet.

Caution

1. Check for water leak after assembly. 2. Make sure the connecting jack is assembled correctly. 3. Make sure the O-ring is assembled correctly.

④

⑥

⑦

⑧

KDB-GOM Series

- 93 -

No 15 Part name Domestic water heat exchanger

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Span the front cover .③ Close the water valve.④ Release the heating water by unscrewing the drain screw below the circulator pump.⑤ Separate the fan unit.⑥ Separate the board holding the ignition transformer and the air pressure switch.⑦ Separate the hot water sensor.⑧ Remove the 2 screws below the front cover fixing the hot water outlet of the hot water heat exchanger.⑨ Separate the 2 pins connecting the hot water heat exchanger and the strainer, the hot water heat exchanger

and the expansion tank.⑩ Separate the hot water heat exchanger from the boiler.

Asse

mbl

y

① Connect the hot water heat exchanger to the hot water outlet from outside.② Fix the hot water heat exchanger to the boiler.③ Fix the hot water outlet of the hot water heat exchanger by screwing the 2 screws.④ Insert the pipe clip at the connecting points.⑤ Fix the board holding the ignition transformer and the air pressure switch.⑥ Open the water, plug in the power cord, replenish water and check for water leak and if everything is fine, close

the front cover.⑦ Plug the boiler into the electric outlet.

Caution

1. Check for water leak after assembly. 2. Make sure the O-ring is assembled correctly.

⑥

④

⑤

⑨⑩

⑧

KDB-GOM Series

- 94 -

No 16-1 Part name Main heat exchanger - 1

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the front cover.③ Release the heating water by unscrewing the drain screw below the circulator pump and release the heating

water from the splitter.④ Separate the board holding the air pressure switch and the ignition transformer by removing one screw.⑤ Separate the front cover of the main heat exchanger by removing the 9 screws in the front and the 2 screws on

the top.⑥ Separate the gas pipe between the gas control valve and the nozzle.⑦ Separate the fan unit according to the manual.⑧ Remove the plastic hose band connecting the expansion tank and the main heat exchanger.⑨ Separate the high limit fuse according to the manual.⑩ Separate the overheating prevention device wire.⑪ Remove the hot water temperature sensor.⑫ Remove the 2 screws at the bottom, the screw on the left and the one on the right, fixing the main heat

exchanger to the front cover.⑬ Separate the main heat exchanger from the boiler.⑭ Separate the exhaust gas notice plate from the main heat exchanger by removing the 6 screws on the top.⑮ Remove the 4 screws fixing the main heat exchanger and separate the main heat exchanger from its front

cover.

47

⑭

⑫

⑬

⑧

⑪

⑦ ⑤

⑨

⑥

④

KDB-GOM Series

- 95 -

No 16-2 Part name Main heat exchanger - 2

Replacement steps

Asse

mbl

y

① Fix the main heat exchanger to the front cover by screwing the 4 screws.② Fix the gas exhaust notice plate to the main heat exchanger by screwing the 6 screws.③ Fix the main heat exchanger to the boiler by screwing the 4 screws on its front cover..④ Insert the plastic hose connecting the expansion tank and put the band on.⑤ Fix the hot water sensor.⑥ Fix the high limit fuse.⑦ Connect the 2 wires of the overheating prevention device.⑧ Assemble the fan unit.⑨ Connect the nozzle.⑩ Connect the ignition transformer and the air pressure switch.⑪ Plug in the power cord and check for water leak during operation. If everything is fine, close the front cover.⑫ Plug in the boiler power cord into the outlet.

Caution

1. Check for water leak after assembly. 2. Check whether all bolts and nuts have been assembled. 3. Check for any shaking while in operation.

KDB-GOM Series

- 96 -

No 17 Part name Power transformer

Replacement steps

Disa

ssem

bly

① Unplug the boiler from the electric outlet.② Open the front cover.③ Separate the harness jack connecting the power transformer and the controller.④ Unscrew the 2 screws fixing the power transformer and separate it from the boiler.

Asse

mbl

y ① Fix the power transformer to the boiler by screwing the 2 screws.② Put the power transformer harness jack into the controller.③ Plug the power cord into the outlet and check its operation. If everything is fine, close the front cover.④ Plug the boiler power cord into the outlet.

Caution

Make sure the connecting jack is connected properly.

④

KDB-GOM Series

- 97 -

1. Exploded Views

2. Part List of each Sections2.1 Front Cover & Cabinet Section

2.2 Main Heat Exchanger Section

2.3 Heating Water Section

2.4 Domestic Hot Water Section

2.5 Gas Supply Section

VII. Part List

- 98 -

15

14

18

13

16

17

22

27

2628

24

25

304431

46

7

9

4

8

3

6

5

38

10

11

40

42

41

36

37

33

39

35

2

32

All GOM(3 kgf/cm )128

53

52

51

1

52

47

45 50

53

39

45

48

49

50

46

47

42

44

43

41

40

34

38

37

35

36

31

32

33

30

29

EGI

1

1

1

1

ALCOT 1

ALDC

ALDC

1

1

1

1

1

ALDC

ALCOT

1

1

1

1

1

TIME UP33-06

1

Silicone

SBHG1

1

1

1

1

NYLON66

Galvanium

Cu

EPDM 1

1

1

1

1

φ8×φ5×620L

L356×φ17×φ25

161/201GOM

161/201GOM

All GOM(CS-0125W)

6

48

49

51

17

25

27

26

24

23

20

21

22

18

19

11

14

16

15

13

12

10

9

7

8

3

4

5

2

1

STS304 1

All GOM(φ25×φ17×4T)

161GOM(10P),201GOM(12P)

C1220T 1

C1220T

C3771BE

PP

EPDM

C1220T

1

1

1

1

1

C3771BE

NYLON66

C3771BE

NYLON66

STS304

1

1

1

1

1

All GOM, 20A(3/4")

161/201GOM

161/201GOM

2

All GOM, 15A(1/2")

All GOM, 15A(1/2")

1

NYLON66

EPDM

C3771BE

EPDM

1

1

1

1

1

ABS

SBHG1

PP

1

1

1

1

All GOM

L394×φ17×φ25

All GOM, 20A(3/4")

All GOM, AC 220V 50/60Hz

All GOM(0~4 kgf/cm )

161/201GOM2

1.2T×250×90×16(WH/SKK)

SCP1

SCP1

PP

SCP1

SCP1

1

1

1

1

All GOM

161/201GOM

34

44

43

21

20

19

12

54

55

CR

CR

1

1

54

55

29

NO. PART NAME MATERIAL Q'TY DESCRIPTION

ROOM THERMOSTAT(FR-5)

Front Cover

Cabinet

Base Bracket, Top

Base Bracket, Bottom

Combustion Air Vent Plate

Flue Exhaust

Combustion Air Vent

Expansion Tank

Heating Pressure Gauge

Power Transformer

Main Controller

Heating Temperature Sensor

Hose, Supply

3-Way Valve

Connection, Heating Supply

Hose, Domestic Water Supply

Pipe, Supply

Domestic Water Heat Exchanger

Pipe, Domestic Water Outlet

Connection, Domestic Water Outlet

Hot Water Flow Switch

Connection, Tap Water Inlet

Pipe, Water Filling

Pipe, Circulation

Hose, Pump Inlet

Strainer, Heating

Connection, Heating Return

Safety Valve

Circulator Pump

Heating Flow Sensor

Hose, Return

Exhaust Duct

Main Heat Exchanger Ass'y

High Limit Sensor

Burner Ass'y

Automatic Air-vent

Manual Air-vent

Hose, Drain

2nd Air Guide Plate

1st Air Guide Plate

Combustion Chamber Ass'y

Electrode Ass'y

Fan Plate

Fan Ass'y

Combustion Chamber Cover Ass'y

Flame Observation Port

High Limit Fuse

Nozzle Holder Ass'y

Modulating Gas Control Valve

Connection, Gas Inlet

Bracket, Ignition Transformer

Air Pressure Switch

Ignition Transformer

Packing, Fan Ass'y

Packing, Nozzle Holder Ass'y

KDB-161/201GOM, EXPLODED VIEW

All GOM

All GOM

All GOM

All GOM

All GOM

All GOM

All GOM

All GOM

All GOM

All GOM

All GOM

실내온도난방수온도40

반복시간C

30

20

난방수온도확인

60

40

80 C

70

10

25

실내온도

3

4

2

0

1

온수전용

FR-5

운전전원

161/201GOM

ON:98°C, OFF:70°C

161/201GOM

All GOM

All GOM, 1/8"PT

161/201GOM

All GOM

161/201GOM

All GOM

All GOM

161GOM(φ62), 201GOM(φ70)

161/201GOM

All GOM

All GOM(195°C)

161(N,φ1.33), 201(N, φ1.46)

161/201GOM, 15A(1/2")

All GOM

All GOM

All GOM

All GOM

All GOM

- 99 -

1NYLON6619 Pipe, Domestic Water Outlet

48

31

15

25

27

28

29

16

14

13

19

18

17 2021

22

9

8

10

3026

2324

49

46

51

52

45

41

40

53

47

1ALDC47 Nozzle Holder Ass'y1

실내온도난방수온도 반복시간

Packing, Fan Ass'y

Packing, Nozzle Holder Ass'y

Combustion Chamber Cover Ass'y

Ignition Transformer

Electrode Ass'y

Fan Plate

52

53

51

49

50

48

ROOM THERMOSTAT(FR-5)

80

70

확인

60

40

20

난방수온도

C

10

40

303

4

2

0

1

C

온수전용

25

실내온도

운전

FR-5

전원

CR

CR

ALCOT

1

1

1

1

1

1

φ8×φ5×720L

L277×φ17×φ25

TIME UP33-06

133 Air Pressure Switch

Manual Air-vent

Auto Air-vent

High Limit Fuse

Main Heat Exchanger Ass'y

Combustion Chamber Ass'y

Modulating Gas Control Valve

Connection, Gas Inlet

2nd Air Guide Plate

1st Air Guide Plate

High Limit Sensor

40

Fan Ass'y

45

46

44

Burner Ass'y42

43

41

38

39

37

Exhaust Duct

35

36

34

1

SBHG1

ALDC

ALDC

ALCOT 1

1

1

1

1

1

Cu

Galvanium

1

1

1

1

1

1

Connection, Domestic Water Outlet

Hot Water Flow Switch

Connection, Tap Water Inlet

Pipe, Water Filling

Pipe, Circulation

Hose, Pump Inlet

Strainer, Heating

Connection, Heating Return

Circulator Pump

Heating Flow Sensor

26

50

29

Hose, Return

Hose, Drain

31

32

30

Safety Valve28

27

22

24

25

23

21

20

1PP

C3771BE

EPDM

NYLON66

Silicone

1

1

1

1

1

1

C3771BE

NYLON66

C3771BE

C1220T

EPDM

C1220T

1

1

1

1

1

1

4

2

3511

33

34

3

5

7

6

32

38

12

39

37

44

43

42

36

DESCRIPTION

L484×φ17×φ25

Combustion Air Vent Plate

Combustion Air Vent

Expansion Tank

Heating Pressure Gauge

Power Transformer

Main Controller

Heating Temperature Sensor

Hose, Supply

Connection, Heating Supply

Hose, Domestic Water Supply

Domestic Water Heat Exchanger

15

Pipe, Supply17

18

16

3-Way Valve14

12

13

8

10

11

9

Flue Exhaust6

7

5

EPDM

C3771BE

EPDM

NYLON66

STS304

C3771BE

1

1

1

1

1

1

1

PP

PP

SBHG1

STS304

1

1

1

1

1

1

1

PART NAME

Base Bracket, Top

Base Bracket, Bottom

1 Front Cover

Cabinet

3

4

2

NO. MATERIAL

SCP1

SCP1

SCP1

SCP1

1

1

1

1

Q'TY

KDB-251/301GOM, EXPLODED VIEW

251/301GOM

251/301GOM (EMBO)

1.2T×250×90×16

All GOM

All GOM

All GOM

All GOM

251/301GOM

All GOM(0~4 kgf/cm )2

All GOM, AC 220V 50/60Hz

All GOM

All GOM

All GOM

All GOM, 20A(3/4")

All GOM

All GOM

251GOM(16P), 301GOM(18P)

All GOM

All GOM

All GOM, 15A(1/2")

All GOM, 15A(1/2")

251/301GOM

All GOM

All GOM(φ25×φ17×4T)

All GOM

All GOM, 20A(3/4")

All GOM(3 kgf/cm )2

All GOM

All GOM

All GOM

All GOM, 1/8"PT

All GOM

251/301GOM

All GOM(195°C)

251/301GOM

MS-1P, 95°C, Automatic

251/301GOM, 20A(3/4")

251/301GOM

251/301GOM

All GOM

251/301GOM

251/301GOM

251(N, φ1.37), 301(N, φ1.50)

All GOM

251/301GOM

251/301GOM

All GOM

All GOM

All GOM

- 100 -

2

65

1

3

Heat Source Set Temperature

Base

OFF

Rad

80Fcl60

85

FMAXCastOFF

551

2

4 0

normal 75

Room Thermosat

FR - 5

18

1217

7

4

3

13

14

8

6

9

10

15

16

5

Front Cover & Cabinet Section(1)

11

A/S Part List(Ⅰ) : KDB-161/201GOM, LNG

NO Part Name Part Code Q'ty Material Remarks1 Room Thermostat C21005075A 1 All GOM, FR-52 Front Cover C21701278A 1 SCP1 KDB-161/201GOM3 Pressure Gauge Sticker C22008023A 1 PC All GOM, 64×64×0.4T4 Rock Ring, Cover C21701095A 2 STS304 KDB-161/201GOM, 1.0T

Cabinet C21701320A 1 SCP1 KDB-161/201GOMBolt C21336012A 25 MSWR3/FZ D4×10L

Base Bracket, Top C21701034B 1 SHP1 All GOM, 16×90×250×1.2TTapping Screw C21336011A 3 MSWR3/FZ D4×8L

Base Bracket, Bottom C21701211A 1 SHP1 All GOMTapping Screw C21336011A 3 MSWR3/FZ D4×8LExpansion Tank C22601010A 1 KDB-161/201GOMTapping Screw C21336004A 2 MSWR3/FZ D5×10L

Combustion Air Vent Plate C21701217A 1 PP All GOMTapping Screw C21336011A 3 MSWR3/FZ D4×8LFlue Exhaust C21701215C 1 STS304 All GOM

Tapping Screw C21336011A 3 MSWR3/FZ D4×8LCombustion Air Vent C21701216A 1 PP All GOM

Tapping Screw C21336011A 3 MSWR3/FZ D4×8LHeating Pressure Gauge C20405004B 1 ABS All GOM

Tapping Screw C21336011A 2 MSWR3/FZ D4×8L13 Rock Ring, Cabinet C21701093A 2 STS304 KDB-161/201GOM, 0.8T

Pow er Transformer C20701060A 1 All GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8LMain Controller C21014104D 1 All GOM, KDC-208-1MTapping Screw C21336001A 2 MSWR3/FZ D4×10L

16 Harness(Wires) Assembly C21405126C 1 KDB-161/201GOM17 Glass Fuse C21744027A 2 All GOM, 250V 3A18 Pow er Cord C21405142A 1 All GOM

5

6

7

8

14

15

9

10

11

12

- 101 -

65

1

0

Set TemperatureHeat Source

60

OFFCast

Rad

Base

OFF

Fcl

55

2

F 4MAX

803

851

75normal

3

Room Thermosat

FR - 5

8

13

12

7

19

18

15

4

Front Cover & Cabinet Section(2)

9

17

16

14

6

10

5

11

2

A/S Part List(Ⅰ) : KDB-251/301GOM, LNG

NO Part Name Part Code Q'ty Material Remarks1 Room Thermostat C21005075A 1 All GOM, FR-5, Ver1.12 Front Cover C21701280B 1 SCP1 KDB-251/301GOM3 Pressure Gauge Sticker C22008023A 1 PC All GOM, 64×64×0.4T4 Rock Ring, Cover C21701296A 2 STS304 KDB-251/301GOM, 1.2T

Cabinet C21701279B 1 SCP1 KDB-251/301GOMBolt C21336012A 25 MSWR3/FZ D4×10L

Base Bracket, Top C21701034B 1 SHP1 All GOM, 16×90×250×1.2TTapping Screw C21336011A 3 MSWR3/FZ D4×8L

Base Bracket, Bottom C21701211A 1 SHP1 All GOMTapping Screw C21336011A 3 MSWR3/FZ D4×8LExpansion Tank C22601011A 1 KDB-251/301GOMTapping Screw C21336004A 2 MSWR3/FZ D5×10L

Combustion Air Vent Plate C21701217A 1 PP All GOMTapping Screw C21336011A 3 MSWR3/FZ D4×8LFlue Exhaust C21701215C 1 STS304 All GOM

Tapping Screw C21336011A 3 MSWR3/FZ D4×8LCombustion Air Vent C21701216A 1 PP All GOM

Tapping Screw C21336011A 3 MSWR3/FZ D4×8LHeating Pressure Gauge C20405004B 1 ABS All GOM

Tapping Screw C21336011A 2 MSWR3/FZ D4×8L13 Rock Ring, Cabinet C21701295A 2 STS304 KDB-251/301GOM, 1.2T

Air Pressure Sw itch C21019038A 1 All GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8L

Pow er Transformer C20701060A 1 All GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8LMain Controller C21014104D 1 All GOM, KDC-208-1MTapping Screw C21336001A 2 MSWR3/FZ D4×10L

17 Harness(Wires) Assembly C21405127C 1 KDB-251/301GOM18 Glass Fuse C21744027A 2 All GOM, 250V 3A19 Pow er Cord C21405142A 1 All GOM

5

6

7

8

14

15

16

9

10

11

12

- 102 -

12

11

8

10

14

9

4

2 3

13

7

1

5

Main Heat Exchanger Section(1)

6

A/S Part List(Ⅱ) : KDB-161/201GOM, LNG

NO Part Name Part Code Q'ty Material RemarksC21703158A 1 KDB-161GOMC21703159A 1 KDB-201GOM

2 Heating Temperature Sensor C21007029A 1 All GOMBolt C21336007A 2 MSWR3/FZ D4×6L

3 Automatic Air Vent C20307013A 1 All GOMPipe Clip C21374024A 1 STS304 24×32×1T

4 Manual Air Vent C20301010A 1 All GOM5 High Limit Sensor C21002020A 1 KDB-161/201GOM, Automatic

Tapping Screw C21332002A 2 D3×8LExhaust Duct C21703116A 1 KDB-161/201GOM

Tapping Screw C21336011A 8 MSWR3/FZ D4×8L7 Burner Assembly C25103072A 1 KDB-161/201GOM8 Drain Hose C21606033A 1 SILICONE KDB-161/201GOM, φ8×φ5×620L

Electrode Assembly C21809040B 1 KDB-161/201GOMElectrode Bracket C21703162A 1 All GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8L

10 Hig Limit Fuse C21007028A 1 All GOMTapping Screw C21336011A 1 MSWR3/FZ D4×8L

11 Fan Packing C21604036A 1 CR All GOMC20802022A 1 KDB-161GOM, φ62C20802023A 1 KDB-201GOM, φ70

Tapping Screw C21336011A 2 MSWR3/FZ D4×8LTapping Screw (Round Head) C21332007A 4 M4×6L

Combustion Chamber Assembly C21703119D 1 ALCOT KDB-161/201GOM1st Air Guide Plate C21703121A 1 EGI All GOM2nd Air Guide Plate C21703123A 1 EGI KDB-161/201GOM

Tapping Screw (Round Head) C21332007A 4 M4×6LTapping Screw C21336011A 13 MSWR3/FZ D4×8LTapping Screw C21336005A 2 MSWR3/FZ D5×8L

Combustion Chamber Cover Assembly C21703120A 1 ALCOT KDB-161/201GOMTapping Screw (Round Head) C21332007A 2 M4×6L

Tapping Screw C21336011A 8 MSWR3/FZ D4×8L

Main Heat Exchanger Assembly1

13

14

Fan Assembly

6

9

12

- 103 -

11

3

1 6

12

13

10

14

Main Heat Exchanger Section(2)

4

5

7

8

2

9

A/S Part List(Ⅱ) : KDB-251/301GOM, LNG

NO Part Name Part Code Q'ty Material RemarksC21703160C 1 KDB-251GOMC21703161C 1 KDB-301GOM

Exhaust Duct C21703141A 1 KDB-251/301GOMTapping Screw C21336011A 8 MSWR3/FZ D4×8L

3 Drain Hose C21606034A 1 SILICONE KDB-251/301GOM, φ8×φ5×720LAutomatic Air Vent C20307013A 1 All GOM

Pipe Clip C21374024A 1 STS304 24×32×1T5 Manual Air Vent C20301010A 1 All GOM

Heating Temperature Sensor C21007029A 1 All GOMBolt C21336007A 2 MSWR3/FZ D4×6L

7 High Limit Sensor C21002023A 1 KDB-251/301GOM, AutomaticHigh Limit Fuse C21007028A 1 All GOMTapping Screw C21336011A 1 MSWR3/FZ D4×8L

Burner Assembly C25103088A 1 KDB-251/301GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8L

Electrode Assembly C21809054B 1 KDB-251/301GOMElectrode Bracket C21703162A 1 All GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8LFan Assembly C20802024A 1 KDB-251/301GOMTapping Screw C21336011A 2 MSWR3/FZ D4×8L

Tapping Screw (Round Head) C21332007A 4 M4×6L12 Fan Packing C21604036A 1 CR All GOM

Combustion Chamber Assembly C25103110A 1 ALCOT KDB-251/301GOM1st Air Guide Plate C21703121A 1 EGI All GOM2nd Air Guide Plate 1 EGI KDB-251/301GOM

Tapping Screw (Round Head) C21332007A 2 M4×6LTapping Screw C21336011A 4 MSWR3/FZ D4×8LTapping Screw C21336005A 2 MSWR3/FZ D5×8L

Combustion Chamber Cover Assembly C21707223A 1 ALCOT KDB-251/301GOMTapping Screw (Round Head) C21332007A 2 M4×6L

Tapping Screw C21336011A 8 MSWR3/FZ D4×8L

11

13

14

6

8

9

10

Main Heat Exchanger1

2

4

- 104 -

10

2

1

3

138

5

6

Heating Water Section

4

11

9

12

7

A/S Part List(Ⅲ) : KDB-161/201/251/301GOM

NO Part Name Part Code Q'ty Material Remarks1 Circulation Pump Assembly C20501017A 1 All GOM2 Pressure Relief Valve C20307014C 1 All GOM3 Heating Flow Sensor C21213011A 1 NY66 All GOM, φ204 Pipe Clip C21374009B 1 STS304 27×34×1T

C40308017A 1 KDB-161/201GOMC40308018A 1 KDB-251/301GOM

Pipe Clip C21374024A 1 STS304 24×32×1TO-ring C21603038A 1 EPDM φ28×φ34×3T

C21708336A 1 C1220T KDB-161/201GOMC21708339A 1 C1220T KDB-251/301GOM

Bolt C21336012A 2 MSWR3/FZ D4×10LC21708338A 1 C1220T KDB-161/201GOMC21708340A 1 C1220T KDB-251/301GOM

8 Pump Inlet Hose C21603041A 1 EPDM All GOM, φ25×77L9 Hose Clip C21374016B 2 SK5 φ23

10 Heating Strainer C20901015A 1 PP All GOM11 O-ring C21606038A 1 NBR P16×2.7T12 O-ring C21610034A 1 SILICONE P19×2.4T

Heating Return Connection C21708306C 1 C3771BE All GOMBolt(Round Head) C21305019A 2 S10C M4×12L

Circulation Pipe

Heating Return Pipe

Water Filling Pipe

13

7

6

5

- 105 -

15

11

13

14

12

10

9

1

2

Domestic Hot Water Section

5

6

4

7

8

3

A/S Part List(Ⅳ) : KDB-161/201/251/301GOM

NO Part Name Part Code Q'ty Material RemarksC21703128A 1 STS304 KDB-161GOMC21703129A 1 STS304 KDB-201GOMC21703144A 1 STS304 KDB-251GOMC21703145A 1 STS304 KDB-301GOM

2 Clip(Domestic Heat Exchanger) C21374014A 4 STS304 1.8T3 Domestic Water Outlet Pipe C21808013A 1 All GOM4 O-ring C21610036A 1 NBR P15×2.4T

Domestic Water Outlet Connection C21708307B 1 C3771BE All GOMBolt(Round Head) C21305019A 2 S10C M4×12L

6 Domestic Water Flow Sw itch C21213016B 1 NY66 All GOM7 Tap Water Inlet Connection C21708308B 1 C3771BE All GOM8 Clip(Domestic Water Flow S/W) C21374015A 1 STS304 0.8T9 Supply Pipe C21708337B 1 C1220T All GOM10 Domestic Water Supply Hose C21603045A 1 EPDM All GOM, φ25×72×126L11 Hose Clip C21374016B 2 SK5 φ2312 3-Way Valve C20313018C 1 All GOM13 O-ring C21610034A 1 SILICONE P19×2.4T

Heating Supply Connection C21708305C 1 C3771BE All GOMBolt(Round Head) C21305019A 2 S10C M4×12L

C40308020A 1 Cu KDB-161/201GOMC40308021A 1 Cu KDB-251/301GOM

Pipe Clip C21374024A 2 STS304 24×32×1T

Domestic Water Heat Exchanger

Heating Supply Pipe

1

5

14

15

- 106 -

Gas Supply Section(1)

8

6

7

1

4

5

3

2

Gas Supply Section(2)

4

6

5

2

3

1

A/S Part List(Ⅴ) : KDB-161/201GOM, LNG A/S Part List(Ⅴ) : KDB-251/301GOM, LNG

NO Part Name Part Code Q'ty Material RemarksC21707273A 1 ALDC KDB-161GOM, φ1.33C21707275A 1 ALDC KDB-201GOM, φ1.46

Tapping Screw C2133011A 2 MSWR3/FZ D4×8LBolt C21336012A 2 MSWR3/FZ D4×10L

2 Nozzle Holder Packing C21604037A 1 CR 3T, 161/201GOMIgnition Transformer Bracket C21701212A 1 EGI KDB-161/201GOM

Tapping Screw C2133011A 2 MSWR3/FZ D4×8LAir Pressure Sw itch C21019038A 1 All GOM, 3T

Tapping Screw C2133011A 1 MSWR3/FZ D4×8LIgnition Transformer C20701031A 1 All GOM, 3T

Tapping Screw C2133011A 2 MSWR3/FZ D4×8L6 Modulating Gas Control Valve C30109017A 1 All GOM, TIME UP33-067 O-ring C21602065A 1 NBR φ17.5×2.7T

Gas Inlet Connection C21708304C 1 ALDC KDB-161/201GOMBolt(Round Head) C21305019A 2 S10C M4×12L

5

8

Nozzle Holder Assembly1

3

4

NO Part Name Part Code Q'ty Material RemarksC21707219A 1 ALDC KDB-251GOM, φ1.37C21707221A 1 ALDC KDB-301GOM, φ1.50

Tapping Screw C2133011A 2 MSWR3/FZ D4×8LBolt C21336012A 2 MSWR3/FZ D4×10L

2 Nozzle Holder Packing C21604045A 1 Forming CR 3T, 251/301GOMIgnition Transformer C20701031A 1 All GOM, 3T

Bolt C21336007A 1 MSWR3/FZ D4×6L4 Modulating Gas Control Valve C30109017A 1 All GOM, TIME UP33-065 O-ring C21602065A 1 NBR φ17.5×2.7T

Gas Inlet Connection C21708335A 1 ALDC KDB-251/301GOMBolt(Round Head) C21305019A 2 S10C M4×12L

Nozzle Holder Assembly

6

3

1