installation instruction - upgnet...packaging until the unit is near the place of installation. rig...

GENERALYORK Model DCE and DCG units are single package airconditioners designed for outdoor installation on a rooftop or aslab and is manufactured under ISO 9002 Quality SystemCertification. The DCE models are cooling only and can beequipped with factory installed electric heaters for cooling /heating applications. The DCG models are gas-fired centralheating furnaces with cooling.The units are completely assembled on rigid, permanentlyattached base rails. All piping, refrigerant charge, and electricalwiring is factory installed and tested. All units require electricpower, duct connections and fixed outdoor air intake damper(units without economizer or motorized damper option only) atthe point of installation.The DCG units additionally require gas connection, installationof the combustion air inlet hood and the flue gas outlet hoods atthe point of installation. The gas-fired heaters have aluminized-steel tubular heat exchangers and spark ignition with provenpilot.Supplemental electric heaters for DCE units have nickel-chrome elements and utilize single point power connections.The following safety precautions apply to DCG units:

INSPECTION

As soon as a unit is received, it should be inspected forpossible damage during transit. If damage is evident, theextent of the damage should be noted on the carrier's freightbill. A separate request for inspection by the carrier's agentshould be made in writing.

REFERENCEAdditional information on the design, installation, operationand service of this equipment is available in the followingreference forms:

• 44-320-10 - Barometric Relief Damper Accessory• 530.18-N6.1V - Propane Conversion Accessory• 530.18-N6.2V - High Altitude Accessory (Nat. Gas)• 530.18-N6.3V - High Altitude Accessory (Propane)

Renewal Parts:

• Refer to the Renewal Parts Manual for complete listing ofreplacement parts on this equipment.

All forms referenced in this instruction may be ordered from:Publications Distribution CenterUnitary Products GroupP.O. Box 1592, York, Pa. 17405

�� SUNLINE 2000–ELECTRIC / ELECTRIC & GAS / ELECTRIC

SINGLE PACKAGE AIR CONDITIONERS(Constant Air Volume)

INSTALLATION INSTRUCTION Supersedes: 530.26-N7YI (795) 530.26-N7YI (299)

MODELS D3CE & D3CG300(WORLD 50 Hz)

035-16191

DCG MODELSHOWN

Installer should pay particular attention to the words: NOTE,CAUTION and WARNING. Notes are intended to clarify or make

FOR YOUR SAFETY

Do not store or use gasoline or other flammable vapors andliquids in the vicinity of this or any other appliance.

FOR YOUR SAFETY

If you smell gas:1. Open windows.2. Don't touch electrical switches3. Extinguish any open flame.4. Immediately call your gas supplier.

CAUTIONTHIS PRODUCT MUST BE INSTALLED IN STRICT COMPLIANCEWITH THE ENCLOSED INSTALLATION INSTRUCTIONS ANDANY APPLICABLE LOCAL, STATE, AND NATIONAL CODESINCLUDING, BUT NOT LIMITED TO, BUILDING, ELECTRICAL,AND MECHANICAL CODES.

WARNINGINCORRECT INSTALLATION MAY CREATE A CONDITIONWHERE THE OPERATION OF THE PRODUCT COULD CAUSEPERSONAL INJURY OR PROPERTY DAMAGE

2 Unitary Products Group

530.26-N7YI

General................................................................................1Inspection ............................................................................1Reference............................................................................1Nomenclature ......................................................................2

INSTALLATIONLimitations ...........................................................................3Location...............................................................................3Rigging and Handling ..........................................................3Clearances ..........................................................................3Ductwork .............................................................................3Fixed Outdoor Air Intake Damper........................................4Condensate Drain ...............................................................4Compressors .......................................................................4Filters...................................................................................4Service Access....................................................................4Thermostat ..........................................................................4Power and Control Wiring ...................................................4Optional Electric Heaters (DCE Models) .............................6Combustion Discharge (DCG Models) ................................6Gas Piping (DCG Models) ...................................................6Gas Connection (DCG Models)...........................................6Vent and Combustion Air Hoods (DCG Models) .................7Optional Econ. / Mot. Damper Rain Hood ..........................7

OPERATIONCooling System .................................................................13Preliminary Operation Cooling ..........................................13Cooling Sequence of Operation ........................................13Safety Controls (Cooling) ..................................................13Electric Heating - Sequence of Operation .........................13Heating Anticipator Setpoints ............................................14Gas Heating - Sequence of Operation ..............................14Safety Controls (Heating) ..................................................14Heat Anticipator Setpoints .................................................15Pre-Start Check List ..........................................................15

START-UPOperating Instructions .......................................................15Post-Start Check List .........................................................15Manifold Gas Pressure Adjustment ...................................15Pilot Checkout ...................................................................16Burner Instructions ............................................................16Burner Air Shutter Adjustment...........................................16Checking Supply Air CFM .................................................16Adjustment of Temperature Rise .......................................17Checking Gas Input ...........................................................17Secure Owner's Approval..................................................17

MAINTENANCE & TROUBLESHOOTINGNormal Maintenance .........................................................18Cleaning Flue Passages and Heating Elements ...............18Troubleshooting.................................................................19

TABLESNo. Description Page1 Unit Application Data.................................. 32 Gas Heat Application Data......................... 63 Pipe Sizing ................................................. 64 Physical Data ............................................. 95 Electrical Data - Basic Units...................... 96 Electrical Data - Units With Elec. Heat...... 97 Supply Air Blower Performance ................ 128 Static Resistances...................................... 129 Blower Motor and Drive Data ..................... 12

10 Heat Anticipator Setpoint ........................... 1411 Electric Heat Capacity By Stage ................ 1412 Limit Control Setting................................... 1413 Gas Rate - Cubic Feet Per Hour ................ 17

FIGURESNo. Description Page1 Typical Rigging........................................... 32 Center of Gravity ........................................ 33 Fixed Outdoor Air Damper ......................... 44 Recommended Drain Piping ...................... 45 Typical Field Wiring .................................... 56 External Supply Connection....................... 67 Bottom Supply Connection......................... 68 Vent and Combustion Air Hoods ................ 79 Adjusting Enthalpy Setpoint ....................... 810 Dimensions and Clearances ...................... 10

Dimensions and Clearances (cont'd) ......... 1111 Gas Valve Piping........................................ 1412 Gas Valve and Controls ............................. 1513 Typical Gas Valve....................................... 1514 Proper Flame Adjustment .......................... 1615 Typical Flame Appearance......................... 1616 Belt Adjustment .......................................... 1617 Pressure Drop versus Supply Air CFM ...... 1718 Typical Flue Baffle Installation.................... 18

TABLE OF CONTENTS

D 3 C G E C4N

PRODUCT NOMENCLATURE

PRODUCT GENERATION

3 = 3rd Generation

PRODUCT CATEGORY

D = Single Package Air Conditioner(Air Cooled)

PRODUCT IDENTIFIER

CG = Gas/ElectricCE = Cooling only or

Electric / Electric

VOLTAGE CODE

50 = 380/415-3-50

NOMINAL HEATINGOUTPUT CAPACITY

300 = 25 Tons

FACTORY INSTALLEDOPTION CODE

EC = Sing. Input EconomizerDK = Diff. Input EconomizerFD = Sing. Input Economizer

w/Power ExhaustCF = Diff. Input Economizer

w/Power ExhaustBG = Motorized Outdoor Air

Damper

2 003 0 5 0

FACTORY INSTALLEDHEAT

A = No HeatN = Natural GasE = Electric

NOMINAL COOLINGCAPACITY

GAS240 = 240 MBH320 = 320 MBH

ELECTRIC018 = 18 KW036 = 36 KW054 = 54 KW072 = 72 KW

LIMITATIONSThese units must be installed in accordance with the followingapplicable national and local safety codes:Refer to Table 1 for Unit Application Data and to Table 2 for GasHeat Application Data.If components are to be added to a unit to meet local codes,they are to be installed at the dealer's and/or the customer'sexpense.

LOCATIONUse the following guidelines to select a suitable location forthese units.1. Unit is designed for outdoor installation only.2. Condenser coils must have an unlimited supply of air.

Where a choice of location is possible, position the unit oneither north or east side of building.

3. For ground level installation, use a level concrete slab witha minimum thickness of 4 inches. The length and widthshould be at least 6 inches greater than the unit base rails.Do not tie slab to the building foundation.

WARNING:Excessive exposure of this furnace tocontaminated combustion air may result inequipment damage or personal injury. Typicalcontaminates include: permanent wave solutions,chlorinated waxes and cleaners, chlorine basedswimming pool chemicals, water softeningchemicals, carbon tetrachloride, Halogen typerefr igerants, c leaning solvents (e.g.perchloroethylene), printing inks, paint removers,varnishes, hydrochloric acid, cements and glues,antistatic fabric softeners for clothes dryers,masonry acid washing materials.

4. Roof structures must be able to support the weight of theunit and its options and/or accessories. Unit must beinstalled on a solid level roof curb or appropriate angle ironframe.

CAUTION: If a unit is to be installed on a roof curb or spe-cial frame other than a YORK roof curb, gasket-ing must be applied to all surfaces that come incontact with the unit underside.

5. Maintain level tolerance to 1/2" maximum across the entirelength or width of the unit.

RIGGING AND HANDLINGExercise care when moving the unit. Do not remove anypackaging until the unit is near the place of installation. Rig theunit by attaching chain or cable slings to the round lifting holesprovided in the base rails. Spreaders, whose length exceedsthe largest dimension across the unit, MUST be used acrossthe top of the unit. Refer to Figure 1.Units may also be moved or lifted with a forklift, from the front orrear only, providing that an accessory skid is used.LENGTH OF FORKS MUST BE A MINIMUM OF 90".

CAUTION: On gas heating units, an adhesive backed label isprovided over the outside of the combustion airinlet opening to prevent moisture from entering theunit which could cause damage to electricalcomponents. Allow this closure label to remain inplace until the combustion air hood is to beinstalled (refer to Figure 8).

Refer to Table 4 for unit weights and to Figure 2 for approximatecenter of gravity.

CLEARANCESAll units require certain clearances for proper operation andservice. Installer must make provisions for adequatecombustion and ventilation air in accordance with nationaland/or applicable provisions of the local building codes. Referto Figure 10 for the clearances required for combustibleconstruction, servicing, and proper unit operation.WARNING:Do not permit overhanging structures or shrubs to

obstruct outdoor air discharge outlet, combustionair inlet or vent outlets.

DUCTWORKDuctwork should be designed and sized according to themethods in Manual Q of the Air Conditioning Contractors ofAmerica (ACCA).A closed return duct system shall be used. This shall notpreclude use of economizers or outdoor fresh air intake. Thesupply and return air duct connections at the unit should bemade with flexible joints to minimize noise.The supply and return air duct systems should be designed forthe CFM and static requirements of the job. They should NOTbe sized to match the dimensions of the duct connections onthe unit.CAUTION: When fastening ductwork to side duct flanges on

unit, insert screws through duct flanges only. DONOT insert screws through casing.Outdoor ductwork must be insulated andwaterproofed.

Refer to Figure 10 for information concerning side and bottomsupply and return air duct openings.

Unitary Products Group 3

530.26-N7YI

INSTALLATION

FIG. 1 - TYPICAL RIGGING

Voltage Variation (Min. / Max.) 380 / 415V 342 / 457V

Wet Bulb Temperature of Air onEvaporator Coil, (Min. / Max.)

°C 15 / 23°F 59 / 73

Dry Bulb Temperature of Air onCondenser Coil, (Min. / Max.)

°C -4 / 52°F 25 / 125

TABLE 1 - UNIT APPLICATION DATA

FIG. 2 - CENTER OF GRAVITY

2337(92")

3461 (136-1/4"

OUTDOORCOIL

1143(45")

1524(60")

FIXED OUTDOOR AIR INTAKE DAMPER

This damper is shipped inside the return air compartment on unitsthat are not provided with an economizer or a motorized damperoption. It is completely assembled and ready for installation. Adamper baffle inside of the hood is adjustable to provide variableamounts of outdoor air intake. Refer to Figure 3.

Gasketing and mounting screws are provided in a parts bagattached to the hood assembly. Apply gasketing to the threeflange surfaces on the hood prior to installing the hood. Extendgasketing 1/4" beyond the top and bottom of the two sideflanges to insure adequate sealing.

Adjusting the damper to the desired air flow may be donebefore mounting the hood into position or (after installation) byremoving the front hood panel or the screen on the bottom ofthe hood. Damper baffle in position 1 will allow approximately10% recirculated air flow, position 2 approximately 15% and, toallow approximately 25%, remove the damper baffle.

On units with bottom return air applications, install the damperassembly over the opening in the side return air access panel.Remove and discard the opening cover and the covering overthe hood mounting holes (used for shipping) before installing.Secure with the screws provided.

On units with side return air applications, install the damperassembly on the return air ductwork as close to the unit aspossible. Cut an opening 16" high by 18" wide in the ductworkto accommodate the damper. Using the holes in the hoodflanges as a template, drill 9/64" dia. (#26 drill) holes into theductwork and secure with the screws provided.

CAUTION: If outdoor air intake will not be required on unitswith bottom return air applications, the damper as-sembly should still be mounted on the side returnair access panel, per the instructions above, to in-sure moisture is not drawn into the unit during op-eration. The covering over the mounting holes onlyneed be removed. Do not remove the openingcover.

CONDENSATE DRAINPlumbing must conform to local codes. Use a sealingcompound on male pipe threads. Install a condensate drainline from the 1" NPT female connection on the unit to an opendrain.

NOTE: The condensate drain line MUST be trapped to pro-vide proper drainage. See Figure 4.

COMPRESSORSUnits are shipped with compressor mountings factory-adjustedand ready for operation.

CAUTION: Do Not loosen compressor mounting bolts.

FILTERS2" filters are supplied with each unit. Filters must always beinstalled ahead of the evaporator coil and must be kept clean orreplaced with same size and type. Dirty filters will reduce thecapacity of the unit and will result in frosted coils or safetyshutdown. Minimum filter area and required sizes are shown inTable 4.

SERVICE ACCESSAccess to all serviceable components is provided by thefollowing removable panels:

• Compressor compartment• Electric Heat compartment - DCE models• Gas Heat compartment (Two panels) - DCG models• Side Supply & Return Air compartments (Two panels)• Blower compartment (Three panels)• Main control box• Filter compartment• Outdoor Air compartment (Two panels)Refer to Figure 10 for location of these access panels.CAUTION: Make sure that all screws and panel latches are

replaced and properly positioned on the unit tomaintain an air-tight seal.

THERMOSTATThe room thermostat should be located on an inside wallapproximately 56" above the floor where it will not be subject todrafts, sun exposure or heat from electrical fixtures orappliances. Follow manufacturer's instructions enclosed withthermostat for general installation procedure. Seven colorcoded insulated wires should be used to connect thermostat tounit.

POWER AND CONTROL WIRINGField wiring to the unit must conform to provisions of thenational code, and/or local ordinances. The unit must beelectrically grounded in accordance with national and/or localcodes. Voltage tolerances which must be maintained at thecompressor terminals during starting and running conditionsare indicated on the unit Rating Plate and Table 1.The internal wiring harness furnished with this unit is anintegral part of design certified unit. Field alteration to complywith electrical codes should not be required.A fused disconnect switch should be field provided for the unit.The switch must be separate from all other circuits. Wire entryat knockout openings require conduit fittings to comply withnational and/or local codes. Refer to Figure 10 for installationlocation. If any of the wire supplied with the unit must bereplaced, replacement wire must be of the type shown on thewiring diagram and the same minimum gauge as the replacedwire.


530.26-N7YI

FIG. 3 - FIXED OUTDOOR AIR DAMPER

FIG. 4 - RECOMMENDED DRAIN PIPING


530.26-N7YI

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FIG. 5 - TYPICAL FIELD WIRING

Wire Size1 AWG. Gauge

22 20 19 18 16

25 40 50 65 100

Maximum Wire Length2 Feet

Notes:

1. Solid, Class II copper wire2. Based on a voltage drop of 1.2 volts per wire.

CONTROL WIRE SIZES

Electrical line must be sized properly to carry the load. Eachunit must be wired with a separate branch circuit fed directlyfrom the meter panel and properly fused.CAUTION: When connecting electrical power and control

wiring to the unit, waterproof type connectorsMUST BE USED so that water or moisture cannotbe drawn into the unit during normal operation. Theabove waterproofing conditions will also applywhen installing a field-supplied disconnect switch.

Refer to Figure 5 for typical field wiring and to the appropriateunit wiring diagram for control circuit and power wiringinformation.

OPTIONAL ELECTRIC HEATERS (DCE Models)The factory installed heaters are wired for single point powersupply. Power supply need only be brought into the single pointterminal block and thermostat wiring to the low voltage terminalblock located in the upper portion of the unit control box.These approved heaters are located within the centralcompartment of the unit with the heater elements extendinginto the supply air chamber. Refer to Figure 10 for access panellocation.

Fuses are supplied, where required, by the factory. Some KWsizes require fuses and others do not. Refer to Table 1 forminmum CFM limitations and to Table 6 for electrical data.

COMBUSTION DISCHARGE (DCG Models)

The products of combustion are discharged horizontallythrough two screened (hooded) openings on the upper gasheat access panel.

GAS PIPING (DCG Models)Proper sizing of gas piping depends on the cubic feet per hourof gas flow required, specific gravity of the gas and the length ofrun. “National codes should be followed in all cases unlesssuperseded by local codes or gas utility requirements. Refer toTable 3.The heating value of the gas may differ with locality. The value

should be checked with the local gas utility.

NOTE: There may be a local gas utility requirement specifyinga minimum diameter for gas piping. All units require a 1inch pipe connection at the entrance fitting.

GAS CONNECTION (DCG Models)The gas supply line can be routed through the knockoutslocated on the front of the unit or through the opening providedin the unit's base. Refer to Figure 10 to locate these accessopenings. Typical supply piping arrangements are shown inFigures 6 and 7. All pipe, fittings, etc. are field-supplied.Two grommets are shipped in the blower compartment (in partsbag taped to the blower housing) of every unit with gas heatand should be used in the knockouts when the gas pipingenters through the front of the unit.After the gas supply piping has been installed, the bottomopening in the unit should be sealed to prevent water fromleaking into the building.Gas piping recommendations:1. A drip leg and a ground joint union must be installed in the

gas piping.2. When required by local codes, a manual shut-off valve may

have to be installed outside of the unit.3. Use wrought iron or steel pipe for all gas lines. Pipe

compound should be applied sparingly to male threadsonly.


530.26-N7YI

FIG. 6 - EXTERNAL SUPPLY CONNECTIONEXTERNAL SHUT-OFF

kWInput Capacity (kW) Output Capacity (kW)

GasRate2

(M3/Hr.)

Temp.Rise °C

AtFull Input 3

0 To608 Meters

AboveSea Level

608 To1,368 Meters

AboveSea Level1

0 To608 Meters

AboveSea Level

608 To1,368 Meters

AboveSea Level1

Max. Min. Max. Min. Max. Max. Min. Max.

87.8 43.9 79.0 39.4 70.0 62.3 7.9 11 28

117.0 58.5 105.3 52.6 93.6 82.1 10.5 17 33

MBHInput Capacity (Mbh) Output Capacity (Mbh)

GasRate2

(Ft.3/Hr.)

Temp.Rise °F

AtFull Input 3

0 To2,000 Feet

AboveSea Level

2,000 To4,500 Feet

AboveSea Level1

0 To2,000 Feet

AboveSea Level

2,000 To4,500 Feet

AboveSea Level1

Max. Min. Max. Min. Max. Max. Min. Max.

300 150 270 135 240 213 279 20 50

400 200 360 180 320 281 372 30 60

1kW (MBH) rating should be reduced at the rate of 4 percent for each 304 meters (1,000 ft.)above 1368 meters (4,500 ft.).

2Based on maximum input and 1075 Btu/Ft3.3The air flow must be adjusted to obtain a temperature rise within the range shown.

TABLE 2 - GAS HEAT APPLICATION DATA

Length in Meters/FeetNominal Iron Pipe Size

25mm (1 in.) 32mm (1-1/4 in.)3.1 / 106.1 / 209.1 / 3012.2 / 4015.2 / 5018.2 / 6021.3 / 7024.3 / 8027.4 / 9030.4 / 100

14.7 / 5209.9 / 3508.1 / 2856.9 / 2456.1 / 2155.5 / 1955.1 / 1804.8 / 1704.5 / 1604.2 / 150

29.7 / 1,05020.7 / 73016.7 / 59014.2 / 50012.5 / 44011.3 / 40010.5 / 3709.9 / 3509.1 / 3208.6 / 305

Maximum capacity of pipe in cubic meters/feet of gas per hour. (Based upon a pressure dropof 0.3 inch water column and 0.6 specific gravity gas).

TABLE 3 - PIPE SIZING

FIG. 7 - BOTTOM SUPPLY CONNECTIONEXTERNAL SHUT-OFF

WARNING:Natural gas may contain some propane. Propane,being an excellent solvent, will quickly dissolvewhite lead or most standard commercialcompounds. Therefore, a special pipe compoundmust be applied when wrought iron or steel pipe isused. Shellac base compounds such as Gaskolacor Stalastic, and compounds such as Rectorseal#5, Cyde's or John Crane may be used.

4. All piping should be cleaned of dirt and scale by hammeringon the outside of the pipe and blowing out the loose dirt andscale. Before initial start-up, be sure that all of the gas linesexternal to the unit have been purged of air.

5. The gas supply should be a separate line and installed inaccordance with all safety codes as prescribed under“Limitations”. After the gas connections have beencompleted, open the main shut-off valve admitting normalgas pressure to the mains. Check all joints for leaks withsoap solution or other material suitable for the purpose.NEVER USE A FLAME.

6. The furnace and its individual manual shut-off valve mustbe disconnected from the gas supply piping system duringany pressure testing of that system at test pressures inexcess of 1/2 psig (3.48kPa).The furnace must be isolated from the gas supply pipingsystem by closing its individual manual shut-off valveduring any pressure testing of the gas supply piping systemat test pressures equal to or less than 1/2 psig (3.48kPa).

7. A 1/8 inch NPT plugged tapping, accessible for test gageconnection, must be installed immediately upstream of thegas supply connection to the furnace.

VENT AND COMBUSTION AIR HOODS(DCG Models)

Two vent hoods and a combustion air hood (with screens) areshipped attached to the blower housing in the blowercompartment. These hoods must be installed to assure properunit function. All hoods must be fastened to the outside of thegas heat access panel with the screws provided in the bag alsoattached to the blower housing.

The screen for the combustion air intake hood is secured to theinside of the access panel opening with four fasteners and thescrews used for mounting the hood to the panel. The top flangeof this hood slips in under the top of the access panel openingwhen installing. Refer to Figure 8.

Each vent hood is installed by inserting the top flange of thehood into the slotted opening in the access panel and securingin place.

OPTIONAL ECONOMIZER/MOTORIZED DAMPERRAIN HOOD

The instruction for the optional economizer/motorized damperrain hood can be found in form 44-320-2. Use theseinstructions when field assembling an economizer rain hoodonto a unit. The outdoor and return air dampers, the damperactuator, the damper linkage, the outdoor and return air dividerbaffles, and all the control sensors are factory mounted as partof the “Factory installed” economizer option.

ENTHALPY SET POINT ADJUSTMENT

Remove the economizer access panel from the unit to checkthe following adjustments. Loosen but do not remove the twopanel latches.

CAUTION: Extreme care must be exercised in turning both thesetpoint and minimum position adjusting screws toprevent twisting them off.

1. The enthalpy set point may now be set by selecting thedesired setpoint shown in Figure 9. Adjust as follows:

• For a single enthalpy operation, carefully turn the setpoint adjusting screw to the “A”, “B”, “C” or “D” settingcorresponding to the lettered curve.

• For a dual enthalpy operation, carefully turn the set pointadjusting screw fully clockwise past the “D” setting.

2. To check that the damper blades move smoothly withoutbinding, carefully turn the minimum position adjustingscrew fully clockwise and then energize and de-energizeterminals “R” to “G”. With terminals “R” to “G” energized,turn the minimum position screw counterclockwise until thedesired minimum position has been attained.

3. Replace the economizer access panel. Reposition the twolatches horizontally and retighten the screws.


530.26-N7YI

VENT AIROUTLETHOODS

SLOTTEDOPENINGS IN ACCESS PANEL

COMBUSTIONAIR INTAKEHOOD

GAS HEATACCESSPANELS

FIG. 8 - VENT AND COMBUSTION AIR HOODS


530.26-N7YI

FIG. 9 - ENTHALPY SETPOINT ADJUSTMENT


530.26-N7YI

MODELD2CE

POWERSUPPLY

HEATER OPTION MINIMUMCIRCUIT

AMPACITY(AMPS)

MAXIMUMOVERCURRENT

DEVICE2

(AMPS)MODEL KW1 STAGES AMPS

300

380-3-50

E018E036E054E072

11.322.633.845.1

1222

17.134.351.468.6

76.076.088.0109.5

909090110

415-3-50

E018E036E054E072

13.526.940.453.8

1222

18.737.456.274.9

76.076.093.998.6

9090100110

1Electric Heat CORRECTION FACTORS:

TABLE 6- ELECTRICAL DATA - UNITS WITH ELECTRIC HEAT

2Dual element time delay fuse or HACR breaker.

VOLTAGELIMITA-TIONS**

POWER SUPPLYVOLTAGE

MIN. MAX.380/415-3-50 342 457

**Utilization Range “A” in accordance with ARI Stan-dard 110.

NOMINAL VOLTAGE VOLTAGE KW CAP. MULTIPLIER415 400 0.93

COMPONENT DESCRIPTIONUNIT

MODEL300

SUPPLY AIRBLOWER

CENTRIFUGAL BLOWERDIA. x WD. (mm) 457 x 381DIA. x WD. (in.) 18 x 15

FAN MOTOR kW / HP 7.5 / 10

INDOORCOIL

ROWS DEEP 4FINS PER 25mm (1 in.) 13.5FACE AREA m2 / Ft.2 2.3/25.0

OUTDOORFANS

(Two Per Unit)

PROPELLER DIA. mm / in. 762 / 30 ea.FAN MOTOR kW / HP 0.7 / 1 ea.

NOMINAL AIRFLOWm3 / s 3.40 ea.CFM 7200 ea.

OUTDOORCOIL

ROWS DEEP 3FINS PER 25mm (1 in.) 15FACE AREA m2 / Ft.2 4.02 / 43.3

COMPRESSOR(Qty. Per Unit) TANDEM (12.5 TON NOMINAL CAPACITY) 2

AIRFILTERS

QUANTITY PER UNIT406 x 508 x 51 (mm)

216 x 20 x 2 (in.)


416 x 25 x 2 (in.)


314 x 20 x 2 (in.)

TOTAL FACE AREA m2 / Ft.2 .9 1/ 21.4

CHARGEREFRIGERANT 22 SYS. #1 (kg. / lbs.) 9.3/20.5

SYS. #2 (kg. / lbs. ) 9.1/20.0*This compressor will be energized first.

TABLE 4 - PHYSICAL DATAWEIGHTS (kg. / lbs. )

BASICUNIT

DCE300(Cooling only)

DCG300(Gas / Electric)

N240 1085 / 2930N320 1348 / 2970

OPTIONS / ACCESSORIES

Electric Heater(Elec/Elec only)

18 KW 11.4 / 2536 KW 13.6 / 3054 KW 15.9 / 3572 KW 18.2 / 40

Economizer 73 / 160Motorized Damper 68 / 150Roof Curb 84 / 185Barometric Damper 20 / 45Wood Skid* 100 / 220

*Allows handling of unit using 90" (2300mm)long forks.

MODEL POWERSUPPLY

COMPRESSORS

COND.FAN

MOTORS#1 & #2

SUPPLYAIR

BLOWERMOTOR

MINIMUMCIRCUIT

AMPACITY(AMPS)

MAXIMUMOVERCURRENT

DEVICE1

(AMPS)(QTY. 2)HP

(Each)FLA

(Each) HP FLARLA(Each)

LRA(Each)

D2CE300D2CG300 380/415-3-50 24 202 1.0 2.1 10 19.0 76 90

NOTES: 1. Dual element, time delay type.

TABLE 5 - ELECTRICAL DATA (BASIC UNIT)


530.26-N7YI

FIG. 10 - DIMENSIONS & CLEARANCES - DCE & DCGCont'd.

All dimensions are in inches. They are sub-ject to change without notice. Certified di-mensions will be provided upon request.

CLEARANCES (mm / in.)

Front 914 / 36"

Back610 / 24" (Less Economizer)1245 / 49" (With Econo-mizer)

Left Side (Filter Access)610 / 24" (Less Economizer)1372 / 54" (With Econo-mizer)

Right Side (Cond. Coil) 914 / 36"Below Unit1 0 / 0"

Above Unit2

1829 / 72" With 914 / 36"Maximum

Horizontal Overhang(For Condenser AirDischarge)

1Units (applicable in U.S.A. only) may be installed on combustible floorsmade from wood or class A, B or C roof covering material.

2Units must be installed oudoors. Overhanging structures or shrubs shouldnot obstruct condenser air discharge outlet.

NOTE:DCE Models: Units and ductwork are approved for zero clearance to com-bustible materials when equipped with electric heaters.

DCG Models: A 1" clearance must be provided between any combustiblematerial and the supply air ductwork for a distance of 3 feet from the unit.

The products of combustion must not be allowed to accumulate within aconfined space and recirculate.

Locate unit so that the vent air outlet hood is at least:

• Three (3) feet above any forced air inlet located within 10 horizontal feet(excluding those integral to the unit).

HOLEOPENING

(DIA.)(mm / in.)

USED FOR

A29 / 1-1/8" KO

Control Wir-ing

Front19 / 3/4" NPS

(Fem.) Bottom

B92 / 3-5/8" KO

Power WiringFront

76 / 3" NPS(Fem.) Bottom

C 60 / 2-3/8" KO Gas Piping (Front)

D 43 / 1-11/16"Hole Gas Piping (Bottom)*

*Opening in the bottom of the unit can be located by the slicein the insulation.

UTILITIES ENTRY DATA

RETURN AIR

SUPPLY AIR

CONDENSER AIR

OUTDOOR AIR(Economizer)

DCEUNITS

1337 (52-5/8")

3461 (136-1/4")

ACCESSORYCOIL GAURDSHOWN

DCGUNITS

1337 (52-5/8")

3461 (136-1/4")

ACCESSORYCOIL GAURDSHOWN


530.26-N7YI

FIG. 10 - DIMENSIONS & CLEARANCES (Cont'd.)- DCE & DCG

DETAIL “X”ACCESSORY SIDE SUPPLY AND RE-

DUCT COVERS - Units are shipped with the bottomduct openings covered. An accessory flange kit is avail-able for connecting side ducts.For bottom duct applications:1. Remove the side panels from the supply and return

air compartments to gain access to the bottomsupply and return air duct covers.

2. Remove and discard the bottom duct covers. (Ductopenings are closed with sheet metal covers exceptwhen the unit includes a power exhaust option. The

covering consists of a heavy black paper composition.)3. Replace the side supply and return air compartment

panels.For side duct applications;1. Replace the side panels on the supply and return air

compartments with the accessory flange kit panels.2. Connect ductwork to the duct flanges on the rear of

the unit.

39-5/8

397155

8"

610 (24") (180)889 (35") (240)

870(34-

ECONOMIZER / MOTORIZED DAMPERRAIN HOOD


530.26-N7YITABLE 7 - SUPPLY AIR BLOWER PERFORMANCE

TABLE 8 - STATIC RESISTANCES*

MODELSIZE

BLOWERRANGE(RPM)

MOTOR1 ADJUSTABLE MOTOR PULLEY FIXED BLOWER PULLEY BELT(NOTCHED)

kW /HP FRAME EFF.

(%)DESIG-NATION

PITCHDIA. mm

(IN.)BORE DESIG-

NATION

PITCHDIA. mm

(IN.)BORE DESIG-

NATION

PITCHLENGTH mm

(IN.)QTY.

300 980 /1170 7.5 / 10 254T 89 1LVP58B70A 157-188(6.2-7.4)2

A2BUSH-

ING1B5V94 241

(9.5)B

BUSHING 5VX840 2134(84) 1

1All motors have a nominal speed of 1450 RPM, a 1.15 service factor and a solid base. They can operate to the limit of their service factor because they are located in the moving air, upstreamof any heating device.

EXTERNAL STATIC PRESSURE DROP

DESCRIPTIONRESISTANCE, Pa / iwg

m3/s / CFM4.25 / 9,000 4.72 / 10,000 5.19 / 11,000

WET COIL 25 / 0.1 25 / 0.1 25 / 0.1GAS HEAT 25 / 0.1 25 / 0.1 25 / 0.1

ELECTRIC HEAT OPTIONS

18 KW 25 / 0.1 25 / 0.1 25 / 0.136 KW 25 / 0.1 50 / 0.2 75 / 0.354 KW 50 / 0.2 75 / 0.3 100 / 0.472 KW 50 / 0.2 100 / 0.4 150 / 0.6

ECONOMIZER OPTION 25 / 0.1 25 / 0.1 25 / 0.1INLET GUIDE VANCES 75 / 0.3 100 / 0.4 125 / 0.5HORIZONTAL DUCT CONNECTIONS 50 / 0.2 75 / 0.3 125 / 0.5

*Deduct these resistance values from the available unit ESP values listed in the respective blower performance table except for Horizontal Duct Connec-tions

(Shaded ). Add these values due to less airflow resistance.

TABLE 9 - BLOWER MOTOR AND DRIVE DATA

945 6.0 1.2 5.6 4.6 0.8 7.0 5.7 0.3 8.4 6.9 - - -975 5.0 1.4 5.9 4.9 1.0 7.3 6.0 0.5 8.8 7.2 - - -1005 4.0 1.6 6.2 5.1 1.2 7.7 6.3 0.7 9.2 7.6 0.1 10.9 8.91040 3.0 1.8 6.6 5.4 1.4 8.1 6.7 0.9 9.7 8.0 0.3 11.4 9.41070 2.0 2.0 6.9 5.7 1.6 8.5 7.0 1.1 10.2 8.3 - - -1100 1.0 2.1 7.3 6.0 1.8 8.9 7.3 1.3 10.6 8.7 - - -1130 0.0 2.3 7.6 6.2 2.0 9.3 7.6 1.5 11.0 9.0 - - -

945 6.0 303 5.6 4.6 198 7.0 5.7 71 8.4 6.9 - - -975 5.0 347 5.9 4.9 244 7.3 6.0 120 8.8 7.2 - - -1005 4.0 391 6.2 5.1 291 7.7 6.3 169 9.2 7.6 25 10.9 8.91040 3.0 443 6.6 5.4 347 8.1 6.7 228 9.7 8.0 87 11.4 9.41070 2.0 489 6.9 5.7 396 8.5 7.0 280 10.2 8.3 - - -1100 1.0 536 7.3 6.0 445 8.9 7.3 332 10.6 8.7 - - -1130 0.0 583 7.6 6.2 495 9.3 7.6 385 11.0 9.0 - - -

945 6.0 1.0 5.6 4.6 0.3 7.0 5.7 - - -975 5.0 1.2 5.9 4.9 0.5 7.3 6.0 - - -1005 4.0 1.4 6.2 5.1 0.7 7.7 6.3 - - -1040 3.0 1.6 6.6 5.4 0.9 8.1 6.7 0.2 9.7 8.01070 2.0 1.8 6.9 5.7 1.1 8.5 7.0 0.4 10.2 8.31100 1.0 2.0 7.3 6.0 1.3 8.9 7.3 0.6 10.6 8.71130 0.0 2.2 7.6 6.2 1.5 9.3 7.6 0.8 11.0 9.0

945 6.0 258 5.6 4.6 87 7.0 5.7 - - -975 5.0 301 5.9 4.9 133 7.3 6.0 - - -1005 4.0 345 6.2 5.1 180 7.7 6.3 - - -1040 3.0 398 6.6 5.4 236 8.1 6.7 43 9.7 8.01070 2.0 444 6.9 5.7 285 8.5 7.0 94 10.2 8.31100 1.0 490 7.3 6.0 334 8.9 7.3 146 10.6 8.71130 0.0 537 7.6 6.2 384 9.3 7.6 199 11.0 9.0

4.72 m 3/sec.ESP(Pa)

OUTPUT(bhp)

INPUT(kW )

ESP(Pa)

OUTPUT(bhp)

INPUT(kW )

ESP(Pa)

OUTPUT(bhp)

INPUT(kW )

ESP(Pa)

OUTPUT(bhp)

INPUT(kW )

ESP(Pa)

ESP(Pa)

INPUT(kW )

OUTPUT(bhp)

INPUT(kW )

D3CG300 UNIT -DOW NFLOW DUCT CONNECTIONS

OUTPUT(bhp)

INPUT(kW )

OUTPUT(bhp)

OUTPUT(bhp)

INPUT(kW )

BLOW ERSPEED(rpm )

PULLEYTURNSOPEN

3.53 m 3/sec. 4.13 m 3/sec.

10000 cfm 11250 cfm

D3CE300 UNIT -DOW NFLOW DUCT CONNECTIONS

BLOW ERSPEED(rpm )

PULLEYTURNSOPEN

3.53 m 3/Sec. 4.13 m 3/Sec. 4.72 m 3/Sec. 5.32 m 3/secESP(Pa)

BLOW ERSPEED(rpm )

PULLEYTURNSOPEN

ESP(iwg)

ESP(iwg)

7500 CFM 8750 cfmOUTPUT(bhp)

OUTPUT(bhp)

INPUT(kW )

INPUT(kW )

INPUT(kW )

ESP(iwg)

ESP(iwg)

OUTPUT(bhp)

OUTPUT(bhp)

INPUT(kW )

D3CE300 UNIT -DOW NFLOW DUCT CONNECTIONS

7500 CFM 8750 cfm 10000 cfmBLOW ERSPEED(rpm )

PULLEYTURNSOPEN

ESP(iwg)

D3CG300 UNIT -DOW NFLOW DUCT CONNECTIONS

ESP(iwg)

OUTPUT(bhp)

INPUT(kW )

INPUT(kW )

ESP(iwg)

OUTPUT(bhp)

COOLING SYSTEMThe cooling section is a complete factory package utilizing anair-cooled condenser. The system is factory-charged withRefrigerant-22.The compressors are hermetically sealed, internally sprungand base-mounted with rubber-insulated hold-down bolts.Compressors have inherent (internal) protection. If there is anabnormal temperature rise in a compressor, the protector willopen to shut down the compressor.

PRELIMINARY OPERATION COOLINGAfter the initial installation, the compressors should be giventhree false starts (energized just long enough to make a fewrevolutions) with 5-7 minutes delay between each start, beforebeing put into full time service.

COOLING SEQUENCE OF OPERATIONNO OUTDOOR AIR OPTIONS - When the room thermostatcalls for “first-stage” cooling, the low voltage control circuit from“R” to “G” and “Y1" is completed to energize compressors #1/2(50% capacity), condenser fan motor #1, and the supply airblower motor (if the fan switch on the room thermostat is set inthe ”AUTO" position).When the thermostat calls for “second-stage” cooling, the lowvoltage control circuit from “R” to “Y2" is completed to energizecompressor #3/4.After the thermostat is satisfied and opens, all components willstop simultaneously. The blower motor will continue to operateif the fan switch on the room thermostat is set in the “ON”position.ECONOMIZER WITH SINGLE ENTHALPY SENSOR - Whenthe room thermostat calls for “first-stage” cooling, the lowvoltage control circuit from “R” to “G” and “Y1" is completed.The ”R" to “G” circuit energizes the blower motor (if the fanswitch on the room thermostat is set in the “AUTO” position)and drives the economizer dampers from fully closed to theirminimum position. If the enthalpy of the outdoor air is below thesetpoint of the enthalpy controller (previously determined),“Y1" energizes the economizer. The dampers will modulate tomaintain a constant supply air temperature as monitored by thedischarge air sensor. If the outdoor air enthalpy is above thesetpoint, ”Y1" energizes compressors #1/2 and condenser fanmotor #1.When the thermostat calls for “second-stage” cooling, the lowvoltage control circuit from “R” to “Y2" is completed. If theenthalpy of the outdoor air is below the setpoint of the enthalpycontroller (i.e. first stage has energized the economizer), ”Y2"will energize compressors #1/2. If the outdoor air is above thesetpoint, “Y2" will energize compressor #3/4.After the thermostat is satisfied and opens, all components willstop simultaneously. The blower motor will continue to operateif the fan switch on the room thermostat is set in the “ON”position.ECONOMIZER WITH DUAL ENTHALPY SENSORS - Theoperation with the dual enthalpy sensors is identical to thesingle sensor except that a second enthalpy sensor is mountedin the return air. This return air sensor allows the economizer tochoose between outdoor air and return air, whichever has thelowest enthalpy value, to provide maximum operatingefficiency.ECONOMIZER (SINGLE OR DUAL) WITH POWEREXHAUST - This system operates as specified above with oneaddition. The power exhaust motor is energized whenever theeconomizer is chosen by the enthalpy sensor for first stage

cooling, “Y1". As always, the ”R" to “G” connection providesminimum position but does not provide power exhaustoperation.MOTORIZED OUTDOOR AIR DAMPERS - This systemoperation is the same as the units with no outdoor air optionswith one exception. When the “R” to “G” circuit is complete, themotorized damper drives open to a position set by the dampermotor adjustment. When the “R” to “G” circuit is opened, thedamper spring returns fully closed.CONTINUOUS BLOWER - Continuous blower operation ispossible by closing the R to G circuit on the thermostat.

SAFETY CONTROLSEach refrigerant system is equipped with the following safetycontrols:1. ASuction Line Freezestat to protect against low evaporator

temperatures due to a low air flow or a low return airtemperature.

2. A High Pressure Cutout Switch to protect againstexcessive discharge pressures due to a blockedcondenser coil or a condenser motor failure.

3. ALow Pressure Switch to protect against loss of refrigerantcharge.

If either one of the above safety controls opens, that individualrefrigerant system will be locked out. The other refrigerantsystem will continue in operation unless it too is effected by thesame fault. The lock out of either system can be reset byopening the 24V circuit either at the room thermostat or at theunit disconnect.

ELECTRIC HEATING - SEQUENCE OF OPERATIONWITH POWER TO UNIT AND THERMOSTAT IN THEHEATING MODESingle-stage heating: (applies only to 18 KW heater, all otherheaters MUST use a two-stage thermostat:)a) If the fan switch is in the “ON” position, the evaporator

blower motor contactor (3M) will be energized throughterminal G to provide continuous blower operation. If thefan switch is in the “AUTO” position, the blower will operateonly when there is a call for heating by the thermostat.

NOTE: All 480V heaters are provided with manual resetbackup protection limits. These will de-energizethe heaters should the primary limit fail to open orthe contactors fail to open in a failure mode.

b) Upon a call for heat by the thermostat, the heater contactor(6M) will be energized. If the second stage of heat isrequired, heater contactor (7M) will be energized.

c) The thermostat will cycle the electric heat to satisfy theheating requirements of the conditioned space.

Two-stage heating: (applies to all heaters except 18 KW):a) If the fan switch is in the “ON” position, the evaporator

blower motor contactor (3M) will be energized throughterminal G to provide continuous blower operation. If thefan switch is in the “AUTO” position, the blower will operateonly when there is a call for heating by the thermostat.

b) Upon a call for first-stage heat by the thermostat, the heatercontactor will be energized.If the second stage of heat is required, heater contactor(7M) will be energized.

c) The thermostat will cycle the electric heat to satisfy theheating requirements of the conditioned space.


530.26-N7YI

OPERATION

HEAT ANTICIPATOR SETPOINTSIt is important that the anticipator setpoint be correct. Too highof a setting will result in longer heat cycles and a greatertemperature swing in the conditioned space. Reducing thevalue below the correct setpoint will give shorter “ON” cyclesand may result in the lowering of the temperture within theconditioned space. Refer to Table 11 for the required heatanticipator setting.

GAS HEATING SEQUENCE OF OPERATIONThe following sequence describes the operation of the gasheat section.

CONTINUOUS BLOWERWith the room thermostat switch set to “ON”, the supply airblower will operate continuously. The normally closed contact“K5-1" provides 24 volt power to the “3M” contactor. The “3M-1,2 & 3" power contacts close and the blower motor operates.INTERMITTENT BLOWERWith the room thermostat system switch set to the “AUTO” or“HEAT” position and the fan switch set to “AUTO”, the supply airblower will operate after the room thermostat calls for heat andthe time delay relay closes.The “TH1" closes, the heat relay ”RW1" is energized. The“RW1-1” power contact closes energizing the line voltage draftmotor. The “RW1-2" contact is also closed. As the speed of thedraft motor reaches approximately 2500 RPM, the centrifugalswitch contact located on the end of the draft motor shaft closesto power the first stage ignition module “IC1”.After a brief pre-purge time, ignition module “IC1" will start thefirst stage ignitor sparking and will open the redundant valvelocated inside the first stage main gas valve “GV1” to allow aflow of gas to only the first stage carryover tube. See Figure 13.Only after the pilot flame has been ignited and the presence ofpilot flame detected at the “IC1” by a signal sent back throughthe flame sensor is sparking terminated and the first stage maingas valve opened.Gas flows into each of the main burners and is ignited from thecarryover tube flame.If “IC1” fails to detect a pilot flame, it will continue to try for amaximum of 85 seconds to ignite the pilot tube. If the pilot flameis not detected, then “IC1" will lock out furnace operation for 5minutes, then retry ignition sequence.At the same time power was supplied to the “RW1”, a parallelcircuit activates “TDR” which closes the “TDR” contact afterapproximately 16 seconds and energizes “K5" which closes”K5-2" and starts the blower by energizing “3M”.

When “TH2" closes, heat relay ”RW2" is energized. The “RW2-1" contact is closed energizing the second stage ignitionmodule ”IC2". “IC2" will immediately start the second stageignitor sparking and will open the redundant valve locatedinside the second stage main gas valve ”GV2" to allow a flow ofgas to the second stage carryover tube. See Figure 13. Onlyafter the pilot flame has been ignited and the presence of pilotflame detected at “IC2" by a signal sent back through the flamesensor is sparking terminated and the main gas valve opened.Gas flows into each of the second stage main burners and isignited from the carryover tube flame.If “IC2" fails to detect a pilot flame, it will continue to try for amaximum of 85 seconds to ignite the pilot tube. If the pilot flameis not detected, then ”IC2" will lock out furnace operation for 5minutes, then retry ignition sequence. Note that the secondstage furnace can operate even if first stage has locked out.When the heating cycle is complete, “TH2" opens de-energizing the ”RW2" then “TH1" opens de-energizing ”RW1"and “TDR”, thus closing all gas valves. The blower motor willcontinue to run (approximately 26 seconds after the furnace isshut down) until “TDR” opens, de-energizing the “K5" relay and”3M" contactor. The draft motor will continue to run for a briefpost-purge cycle.

SAFETY CONTROLSThe control circuit includes the following safety controls:1. Limit Control (LS). This control is located inside the heat

exchanger compartment and is set to open at thetemperature indicated in Table 12. It resets automatically.The limit switch operates when a high temperaturecondition, caused by inadequate supply air flow occurs,thus shutting down the ignition control and closing the maingas valves and energizing the blower.

2. Centrifugal Switch (CS). If the draft motor should fail, thecentrifugal switch attached to the shaft of the motorprevents the ignition controls and gas valves from beingenergized.

3. Redundant Gas Valve. There are two separate gas valvesin the furnace. Each valve contains a main and a redundantvalve. The redundant valves are located upstream of themain gas valves. Should either or both of the main gasvalves fail in the open position the redundant valves serveas back-ups and shuts off the flow of gas.

4. Flame Sensor Rod / 100% Ignition Control Lock-Out. Theflame rods and controls are located per Figure 14. If anignition control fails to detect a signal from the flame sensorindicating the pilot flame is properly ignited, then the maingas valve will not open. It will continue to try and ignite thepilot for a maximum of 85 seconds, then if the pilot flame isnot detected, the ignition control will lock out furnaceoperation until 24V power is removed from the moduleeither at the unit or by resetting the room thermostat.

5. Rollout Switch. This switch is located above the mainburners in the control compartment which in the event of asustained main burner rollout shuts off and locks out bothignition controls closing both gas valves. The ignition


530.26-N7YI

GASVALVE

GAS MAIN

MAIN VALVE

TO MAINBURNER

REDUNDANTVALVE

TO PILOT BURNER

FIG. 11 - GAS VALVE PIPING

HEATERKW VOLTAGE

SETTING, AMPSTH1 TH2

18

380/415-3-50

0.29 -36 0.29 0.2954 0.29 0.2972 0.29 0.29

TABLE 10 - HEAT ANTICIPATOR SETTING

Capacity, Kw / MBH Limit ControlOpens, °C / °FInput Output

88 / 300 70 / 240 108 / 195117 / 400 94 / 320 108 / 195

TABLE 12 - LIMIT CONTROL SETTING

ELEC.HEAT

MODELNBR

TOTAL HEATOUTPUT, kW

OUTPUT, kW, BY STAGE

W1 W2

380V 400V 415V 380V 400V 415V 380V 400V 415

A 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

E018 11.3 12.5 13.5 11.3 12.5 13.5 0.0 0.0 0.0

E036 22.6 25.0 26.9 11.3 12.5 13.5 11.3 12.5 13.5

E054 33.8 37.5 40.4 11.3 12.5 13.5 22.6 25.0 26.9

E072 45.1 50.0 53.8 22.6 25.0 26.9 22.6 25.0 26.9

TABLE 11 - ELECTRIC HEAT CAPACITY BY STAGE

controls lock out furnace operation until 24V power isremoved from the controls either at the unit or by resettingthe room thermostat. Note the auto reset rollout switchmust reset before allowing furnace operation.

OPERATING INSTRUCTIONS

CAUTION: This furnace is equipped with an intermittent pilotand automatic re-ignition system. DO NOT attemptto manually light the pilot.

TO LIGHT PILOT AND MAIN BURNERS:

1. Turn “off” electric power to unit.

2. Turn room thermostat to lowest setting.

3. Turn gas valve knob to “on” position.

4. Turn “on” electric power to unit.

5. Set room thermostat to desired temperature.(If thermostat “set” temperature is above roomtemperature, pilot burner ignition will occur and, after aninterval to prove pilot flame, main burners will ignite).

TO SHUT DOWN:

1. Turn “off” electric power to unit.

2. Depress knob of gas valve while turning to “off” position.

POST-START CHECK LIST (GAS)

After the entire control circuit has been energized and theheating section is operating, make the following checks:

1. Check for gas leaks in the unit piping as well as the supplypiping.

2. Check for correct manifold gas pressures. See “CheckingGas Input”.

3. Check the supply gas pressure. It must be within the limitsshown on rating nameplate. Supply pressure should bechecked with all gas appliances in the building at full fire. Atno time should the standby gas line pressure exceed 13",nor the operating pressure drop below 5.0" for natural gas

units. If gas pressure is outside these limits, contact thelocal gas utility for corrective action.

MANIFOLD GAS PRESSURE ADJUSTMENT

Small adjustments to the high-fire gas flow may be made byturning the pressure regulator adjusting screw on theautomatic gas valve. Refer to Figure 15.

Adjust as follows:

1. Remove the cap on the regulator. It's located next to thepush-on electrical terminals.

2. To decrease the gas pressure, turn the adjusting screwcounterclockwise.

3. To increase the gas pressure, turn the adjusting screwclockwise.

NOTE: The correct manifold pressure for these furnaces is3.65 IWG ±0.3.


530.26-N7YI

FIG 12-GAS VALVE AND CONTROLS

HEAT ANTICIPATOR SETPOINTSIt is important that the anticipator setpoint be correct. Too high ofa setting will result in longer heat cycles and a greatertemperature swing in the conditioned space. Reducing thevalue below the correct setpoint will give shorter “ON” cyclesand may result in the lowering of the temperture within theconditioned space.

PRE-START CHECK LIST

Complete the following checks before starting the unit.

1. Check the type of gas being supplied. Be sure that it is thesame as listed on the unit nameplate.

2. Make sure that the vent and combustion air hoods havebeen properly installed.

Gas Valve Anticipator Setpoint1st Stage 2nd Stage

Honeywell VR84400.30 amp 0.11 amp

White-Rodgers 36C68

START-UP

FIG. 13 - TYPICAL GAS VALVE

ON-OFF CONTROL

HIGH FIRE ADJ.(UNDER SCREW)

PILOT ADJ.(UNDER SCREW)

PILOT CHECKOUT

The pilot flame should envelope the end of the flame sensor.Refer to Figure 14. To adjust pilot flame, (1) remove pilotadjustment cover screw, (2) increase or decrease theclearance for air to the desired level, (3) be sure to replacecover screw after adjustment to prevent possible gas leakage.

Put the system into operation and observe through completecycle to be sure all controls function properly.

BURNER INSTRUCTIONS

To check or change burners, pilot or orifices, CLOSE MAINMANUAL SHUT-OFF VALVE AND SHUT OFF ALL ELECTRICPOWER TO THE UNIT.

1. Remove the screws holding either end of the manifold tothe burner supports.

2. Open the union fitting in the gas supply line just upstream ofthe unit gas valve and downstream from the main manualshut-off valve.

3. Remove the gas piping closure panel.

4. Disconnect wiring to the gas valves and spark ignitors. Re-move the manifold-burner gas valve assembly by lifting upand pulling back.

Burners are now accessible for service.

Reverse the above procedure to replace the assemblies. Makesure that burners are level and seat at the rear of the heatexchanger.

BURNER AIR SHUTTER ADJUSTMENT

Adjust burner shutters so no yellow flame is observed in theheat exchanger tubes. Refer to Figure 14.

CHECKING SUPPLY AIR CFM

The RPM of the supply air blower will depend on the requiredCFM, the unit accessories or options and the static resistances ofboth the supply and the return air duct systems. With thisinformation, the RPM for the supply air blower and the motorpulley adjustment (turns open) can be determined from theblower performance data in Table 7.

Note the following:

1. The supply air CFM must be within the limitations shown inTable 1.

2. Pulleys can be adjusted in half turn increments.

3. The tension on the belts should be adjusted as shown inFigure 16.

Start the supply air blower motor. Adjust the resistances in boththe supply and the return air duct systems to balance the airdistribution throughout the conditioned space. The jobspecifications may require that this balancing be done bysomeone other than the equipment installer.

To check the supply air CFM after the initial balancing has been

completed:

1. Remove the two 5/16" dot plugs from the blower motor andthe filter access panels shown in Figure 10.

2. Insert at least 8" of 1/4 inch tubing into each of these holesfor sufficient penetration into the air flow on both sides ofthe indoor coil.

NOTE: The tubes must be inserted and held in a positionperpendicular to the air flow so that velocity pres-sure will not affect the static pressure readings.

3. Using an inclined manometer, determine the pressure dropacross a dry evaporator coil. Since the moisture on anevaporator coil may vary greatly, measuring the pressuredrop across a wet coil under field conditions would be inac-curate. To assure a dry coil, the compressors should be de-activated while the test is being run.


530.26-N7YI

FIG. 14 - PROPER FLAME ADJUSTMENT

FIG. 15 - TYPICAL FLAME APPEARANCE

FIG.[f#] - BELT ADJUSTMENT

4. Knowing the pressure drop across a dry coil, the actualCFM through the unit and clean 2" filters, can be deter-mined from the curve in Figure 17.

WARNING:Failure to properly adjust the total system air quan-tity can result in extensive blower damage.

After readings have been obtained, remove the tubes andreinstall the two 5/16" dot plugs that were removed in Step 1.

NOTE: DE-ENERGIZE THE COMPRESSORS BEFORE TAKING ANY TESTMEASUREMENTS TO ASSURE A DRY INDOOR COIL.

ADJUSTMENT OF TEMPERATURE RISE

The temperature rise (or temperature difference between thereturn air and the heated air from the furnace) must lie within therange shown on the ETL rating plate and the data in Table 2.

After the temperature rise has been determined, the cfm can becalculated as follows:

After about 20 minutes of operation, determine the furnacetemperature rise. Take readings of both the return air and theheated air in the ducts (about six feet from the furnace) wherethey will not be affected by radiant heat. Increase the blowercfm to decrease the temperature rise; decrease the blower cfm

to increase the rise. Refer to Table 10 for blower motor anddrive data.

BELT DRIVE BLOWERAll units have belt drive single-speed blower motors. Thevariable pitch pulley on the blower motor can be adjusted toobtain the desired supply air CFM. Tighten belts enough toprevent slipping. but do not over tighten. Belt deflection shouldbe between 1/4" and 1/2" per foot. Refer to Table 8 for blowermotor and drive data.

CHECKING GAS INPUT

NATURAL GAS

1. Turn off all other gas appliances connected to the gas meter.

2. With the furnace turned on, measure the time needed forone revolution of the hand on the smallest dial on the meter.A typical gas meter usually has a 1/2 or a 1 cubic foot testdial.

3. Using the number of seconds for each revolution and thesize of the test dial increment, find the cubic feet of gasconsumed per hour from Table 13.

If the actual input is not within 5% of the furnace rating (withallowance being made for the permissible range of theregulator setting), replace the orifice spuds with spuds of theproper size.

NOTE To find the Btu input, multiply the number of cubic feet ofgas consumed per hour by the Btu content of the gas inyour particular locality (contact your gas company for thisinformation - it varies widely from city to city.)

NORMAL MAINTENANCE

CAUTION: Prior to any of the following maintenance proce-dures, shut off all electric power to the unit to pre-vent personal injury.


530.26-N7YI

CFMBtuh Input x 0.8

=108. .x F Temp Riseo

SECURE OWNER'S APPROVAL: When the system is functioning properly, secure the owner's approval. Show him the locationof all disconnect switches and the thermostat. Teach him how to start and stop the unit and how to adjust temperature settingswithin the limitations of the system.

FIG. 17 - PRESSURE DROP ACROSS A DRY INDOORCOIL VS SUPPLY AIR CFM

Secondsfor One

Rev.

Size of Test Dial

1/2 cu. ft. 1 cu. ft.

46810

450300228180

900600450360

1214161820

15012911310090

300257225200180

22242628

82756964

164150138129

Example: By actual measurement, it takes 13 seconds for the hand on the 1-cubicfoot dial to make a revolution with just a 300,000 Btuh furnace running. Readacross to the column in the table above, headed “1 Cubic Foot”, where you will seethat 278 cubic feet of gas per hour are consumed by the furnace at that rate. Multi-ply 278 x 1050 (the Btu rating of the gas obtained from the local gas company). Theresult is 292,425 Btuh, which is close to the 300,000 Btuh rating of the furnace.

TABLE 13 - GAS RATE - CUBIC FEET PER HOUR

Periodic maintenance normally consists of changing orcleaning filters and (under some conditions) cleaning the mainburners.FILTERS - Inspect once a month. Replace disposable or cleanpermanent type as necessary. DO NOT replace permanenttype with disposable. The dimensional size of the replacementfilter must be the same as the replaced filter.MOTORSOutdoor fan motors are permanently lubricated and require nomaintenance.Ventor motor is factory lubricated for an estimated 10 year life.Indoor Blower Motor and Drive - The indoor blower motorfeatures ball bearings that do not require periodic lubrication.Periodic lubrication of the motor and bearings can extend thelife of components but is optional.

CAUTION: Damage can occur if the bearings are overlubri-cated. Use grease sparingly.

WARNING:Perform all maintenance operations on the blowermotor with electric power disconnected from theunit. Do not attempt to lubricate bearings with theunit in operation.

On an annual basis, check the motor for accumulations of dust,etc. that may block the cooling slots in the motor shell. Checkfor loose, damaged or misaligned drive components. Checkthat all mounting bolts are tight. Replace defective parts asrequired.If desired, every three years remove both pipe plugs at eachend shell and clean out any hardened grease or foreign matter.Replace one plug on each end with a clean grease fitting. Usinga low pressure grease gun, pump grease (Chevron SRI-2 orequivalent) into the bearing cavity until new grease shows atthe open port. Do not over lubricate. Run the motor for tenminutes until excess grease is purged from the cavity. Replacethe plugs.Units are supplied with blower shaft bearings that do notrequire maintenance but may be relubricated if desired. Everythree years, using a low pressure grease gun, pump greaseinto the bearing grease fitting until grease just begins to show atthe seals. Do not over lubricate. Use any lithium base greaserecommended for ball bearing service.OUTDOOR COIL - Dirt should not be allowed to accumulate onthe outdoor coil surface or other parts in the air circuit. Cleaningshould be as often as necessary to keep coil clean. Use abrush, vacuum cleaner attachment, or other suitable means. Ifwater is used to clean coil, be sure electric power to the unit isshut off prior to cleaning.

NOTE: Exercise care when cleaning the coil so that the coilfins are not damaged.

Do not permit the hot condenser air discharge to be ob-structed by overhanging structures of shrubs.

GAS HEATING UNITS

BURNER & PILOT - Periodically (at least annually at thebeginning of each heating season) make a visual check of thepilot and main burner flame. If necessary, adjust main burnerprimary air shutters to give a distinct, sharp blue flame asexplained under “BURNER AIR SHUTTER ADJUSTMENT”. Ifit is not possible to adjust for the proper flame, the burners mayneed cleaning.

TO CLEAN BURNERS - Remove them from the furnace asexplained in “Burner Instructions”. Clean burners with hotwater applied along top of the burner.COMBUSTION AIR DISCHARGE - Visually inspect dischargeoutlet periodically to make sure that the buildup of soot and dirt

is not excessive. If necessary, clean to maintain adequatecombustion air discharge.

CLEANING FLUE PASSAGES AND HEATING ELEMENTS

With proper combustion adjustment the heating element of agas fired furnace will seldom need cleaning. If the elementshould become sooted, it can be cleaned as follows:1. Remove the burner assembly as outlined in “BURNER

INSTRUCTIONS”.2. Remove the roof over the gas heat section.3. At the top plate from the top draft blower housing and the

top draft blower wheel.4. Remove the screws holding the top of the flue collector box.

Carefully remove the top of the flue collector box withoutripping the adjacent insulation. Then remove the centerdivider plate separating the upper and lower flue boxes.

5. On the inside of the flue collector box, remove the fluebaffles from the tube interiors. Note the last bend of thebaffle fits tightly against the tube forcing the end of thebaffle to lock into the tube collar. This collar is formed whenthe tube is expanded into the end sheet. To remove, movethe end of the baffle toward the center of the tube releasingthe end of the baffle from the tube collar, then pull straightout of the tube. Refer to Figure 20.

6. Using a wire brush on a flexible wand, brush out the insideof each heat exchanger from the burner inlet and flue outletends.

7. Brush out the inside of the flue collector box and the fluebaffles.

8. Run the wire brush down the vent hoods from the fluecollector end.

9. If soot build-up is particularly bad, remove the vent motorand clean the wheel and housings. Run the wire brushdown the flue extentions at the outlet of the vent housings.

10. After brushing is complete, blow all brushed areas with airor nitrogen. Vacuum as needed.

11. Replace parts in the order they were removed in Steps 1thru 4.

12. When replacing the center and top of the flue collector box,be careful not to tear the adjoining insulation.

13. Ensure that all seams on the vent side of the combustionsystem are air tight. Apply a high temperature (+500°F)sealing compound where needed.

WARNING:Troubleshooting of components necessarily re-quires opening the electrical control box with thepower connected to the unit. Use extreme carewhen working with live circuits! Check the unitnameplate for the correct line voltage and set the


530.26-N7YI

MAINTENANCE

FIG. 18 - TYPICAL FLUE BAFFLE INSTALLATION

volt meter to the correct range before making anyconnections with line terminals.

WARNING:Prior to any of the following maintenance proce-dures, shut off all electric power to the unit to pre-vent personal injury.

CAUTION: Label all wires prior to disconnection when servic-ing controls. Wiring errors can cause improper anddangerous operation. Verify proper operation afterservicing.

NOTE: To find the Btu input, multiply the number of cubic feet ofgas consumed per hour by the Btu content of the gas inyour particular locality (contact your gas company for thisinformation - it varies widely from city to city.)

1. The indoor blower motor is a non-inherently protectedthree-phase motor. Protection is provided by an overloadrelay for overcurrent and fuses for short circuit. If the motorfails to run, check the line voltage circuit and control voltagecircuit per the following procedure:

a. If the Indoor Blower Motor does not operate, checkvisually that contactor 3M is pulled in. If so, check forline voltage between all three phases at the line termi-nals of the Blower Overload Relay (BOR). If line voltageis found, check the leads to the blower motor for opencircuit. If line voltage is found at the motor leads (insidethe conduit box on the motor shell), disconnect the mo-tor and check for open windings per the motor wiringdiagram. If open windings are found, replace the motor.If line voltage is not found at the BOR, trace the leadsback to the field supply terminal block, checking for anopen circuit or blown fuses.

b. If the contactor 3M is not pulled in, check for control volt-age (24V) at the 3M coil. If voltage is found, replace thecontactor. If control voltage is not found at 3M, check forvoltage across terminals 95 & 96 of the BOR. If voltageexists, the BOR is open on overload. The BOR shouldbe set to the auto reset position. The BOR must cooldown in order to reset. If the BOR will not reset, replacethe BOR. If the BOR resets and 3M pulls in, but the in-door blower motor will still not run, refer to para. (a) fortroubleshooting the line voltage supply circuit. If controlvoltage is not found at the BOR, trace the circuit back tothe relay board and thermostat per the unit wiring dia-gram. Replace any defective components.

2. Draft motor operates and furnace lights but supply airblower does not start after a short time delay with roomthermostat fan switch set to “AUTO”.

a. Set fan switch to “ON”. If blower motor runs, go to Step f. Ifit does not, check to see if line voltage is being suppliedto the contacts of the contactor (3M), and if thecontactor is pulled in. Check for loose wiring.

b. If contactor (3M) is pulled in, proceed with the trouble-shooting steps indicated in Step 1 above.

c. If (3M) is pulled in and the blower motor still does notrun, replace the blower motor.

d. If (3M) is not pulled in, check for 24 volts at the (3M) coil.If 24 volts is present, replace the (3M) contactor.

e. If 24 volts is not present at the (3M) coil, check for loose24 volt wiring back to the relay board. Check control wir-ing to the room thermostat. If all is fine, replace the relayboard.

f. If the blower motor runs with the fan switch in the “ON”position but does not run soon after the furnace has ig-nited with the fan switch in the “AUTO” position, checkfor loose 24 volt wiring between the relay board in themain control box, the Mate-N-Lok connector in the par-tition between the evaporator and gas heat sectionsand the time delay relay (TDR).

g. If all control wiring is fine, check for 24 volts at the relayboard. If 24 volts is present, replace the relay board. If24 volts is not present, replace the (TDR) relay.

NOTE: The furnace may shut itself down on a high tempera-ture condition during the procedure, but this will not ef-fect the test if it is done within 5 minutes of furnaceshut-down.

3. The supply air blower operates but the draft motor does notwhen the room thermostat is set to call for heat and the fanswitch in the “ON” position.

a. The draft motor has inherent protection. If the motor shellis hot to the touch, wait for the internal overload to reset.

b. If the motor shell is cold with the room thermostat call-ing for heat, check for line voltage at the motor's Mate-N-Lok connector attached to the evaporator partition. Ifline voltage is present, replace the draft motor.

c. If line voltage is not present, check for line voltage at theheat relay (RW1) contacts in the main control box andcheck to see if the (RW1) is pulled in.

d. If the (RW1) relay is pulled in, check for a loose line volt-age connection.

e. If the (RW1) relay is not pulled in, check for 24 volts atthe (RW1) coil. If 24 volts is present, replace the (RW1)relay. If 24 volts is not present, check for a loose 24 voltconnection back to the relay board and check the con-nections from the room thermostat to the relay board. Ifall connections are correct, replace the relay board.

4. The draft motor runs but the furnace does not light and thesparker does not spark.

a. The ignition control (IC1, IC2) may be locked out due toeither a flame roll out or 100% shut off. These safetyfeatures are described above. If lock-out has occurred,24V must be removed from the ignition controls. This isdone at the unit or by resetting the room thermostat. Af-ter resetting 24V, check for proper furnace operation. Iflock-out continues to occur, locate the source of theproblem and correct.

b. Check all 24 volt connections from the relay board toand in the gas heat section. Check low voltage connec-tions to the (TDR) located in the control box.


530.26-N7YI

TROUBLESHOOTING

Cont'd.

c. If the furnace is hot, it may be out on an over-temperature condition, wait for limit reset.

d. If the furnace is cold, check for 24 volts at wire 241 at-tached to the time delay relay (TDR) located in the maincontrol box. If 24 volts is not found, replace the TDR re-lay.

e. If 24 volts is found at wire 241, remove the wires at-tached to the (TDR) and with a VOM, check for continu-ity across contacts 1 and 2. If none is found, the (TDR) isopen and must be replaced. If there is continuity, re-attach the wires.

With the draft motor running, check for 24 volts at termi-nal 4 of (RW1-2) and (RW2-1). If 24 volts is not present,the centrifugal switch (CS) has not closed or has gonebad. Check the line voltage to the unit - if it is correct, re-place the draft motor. If line voltage is low, call the powercompany.

f. Check for 24V at terminal 2 of (RW1-2 and RW2-1). If24V is not present, check for 24V at (RW1 and RW2) re-lay coils. If these relays are pulled in, then check for aloose connection at terminal 2 and terminal 4 of eachrelay. If no problem is found, then replace (RW1 and/orRW2) as required.

g. If 24 volts is present at the ignitor controls, check allcontrol wiring at the ignitor controls and the high tensionwire to the ignitors. Check that the ground wires fromthe ignitor controls, the gas valves and pilot burners areall intact and making good electrical connection. Checkto make sure that the ceramic insulator on the pilot igni-tors or sensors is not broken or cracked, if all are intact,replace the ignition control IC1 or IC2.

5. The draft motor runs and the sparker sparks at the pilotburner but the pilot does not ignite and a gas odor is notdetected at the draft motor outlet.

a. Check to make sure gas is being supplied to the unit.Make sure that the gas pressure to the unit is within theproper limits as described in the “POST START CHECKLIST” and that the pilot adjust screw is allowing someflow of gas as described in “PILOT CHECKOUT”.

b. Check all wiring between the ignitor control and the gasvalve. Check to make sure the ground connections areintact.

c. If the wiring is intact, check for 24 volts across terminals“PV” and “COMMON” on the ignitor control. If 24 volts isnot present, replace the ignitor control.

d. If 24 volts is present, remove the pilot burner andremove the pilot orifice from the pilot burner. The orificeis removed in the direction opposite the flow of gas.Inspect the orifice for obstruction. If it is clear, replacethe main gas valve.

6. The sparker sparks at the pilot burner but the pilot does notignite and a gas odor is detected at the draft motor outlet.

a. Adjust the pilot adjust screw on the gas valve as de-scribed in “PILOT CHECKOUT”.

b. Check the supply pressure as described in “POSTSTART CHECK LIST”. Make adjustments as neces-sary.

c. Check the pilot orifice for obstruction as described inpara. 5d. Clean as needed but the problem should notbe the gas valve.

7. The pilot burner ignites but the sparker continues to sparkand the main burners do not ignite.

a. Make the same checks and adjustment as described inpara. 6.

b. Make sure that the pilot burner is not bent or damaged.

c. Make sure that the ground connections at the pilotburner, gas valve and ignitor control are intact. Checkthe high tension wire for good electrical connection. Ifall are intact, replace the ignitor module.

8. The pilot burner lights and the spark stops but the mainburners do not light.

a. Check electrical connections between the ignitor con-trol and the gas valve. If intact, check for 24 volts acrossterminals “MV” and “COMMON” terminals. If no voltagedetected, replace ignitor control. If voltage is present,replace gas valve.

9. Furnace lights with roll-out or one burner has delayed igni-tion.

a. Make sure that the pilot burner is aligned properly withthe carryover as described in “PILOT CHECKOUT”.

b. Make sure that the carryovers on adjoining burners arescrewed fast and are level with respect to one another.

10. Main burners light but exhibit erratic flame characteristics.

a. Adjust air shutters as described in “BURNER AIRSHUTTER ADJUSTMENT”.

b. Check the main burner orifices for obstruction andalignment. Removal procedure is described in“BURNER INSTRUCTIONS”. Clean or replace burnerorifices and burners as needed.

TROUBLESHOOTING - Cont'd.

Unitary Products Group5005 York Drive, Norman, Oklahoma 73069Subject to change without notice. Printed in U.S.A.Copyright by York International Corporation 1999. All Rights Reserved. Code: SBY 530.26-N7YI

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