model dsh horizontal r-410a supersedes: 145.32-iom2 (908...

Model DSH Horizontal R-410A

Supersedes: 145.32-IOM2 (908) Air Conditioning Units Form 145.32-IOM3 (412)

MODEL DSH024B-096B HORIZONTAL R-410A

AIR CONDITIONING UNITS INSTALLATION INSTRUCTIONS

B Style

FORM 145.32-IOM3 (412)

2 JOHNSON CONTROLS

IMPORTANT! READ BEFORE PROCEEDING!

GENERAL SAFETY GUIDLINES

This equipment is a relatively complicated apparatus. During installation, operation, maintenance or service, individuals may be exposed to certain components or conditions including, but not limited to: refrigerants, oils, materials under pressure, rotating components, and both high and low voltage. Each of these items has the potential, if misused or handled improperly, to cause bodily injury or death. It is the obligation and respon-sibilty of operating/service personnel to identify and recognize these inherent hazards, protect themselves, and proceed safely in completing their tasks. Failure to comply with any of these requirements could result in serious damage to the equipment and the property in

which it is situated, as well as sever personal injury or death to themselves and people at the site. This document is intended for use by owner-authorized operating/service personnel. It is expected that this individual possesses independent training that will en-able them to perform their assigned tasks properly and safely. It is essential that, prior to performing any task on this equipment, this individual shall have read and understood this document and any referenced materials. This individual shall also be familiar with and comply with all applicable governmental standards and regulations pertaining to the task in question.

SAFETY SYMBOLS

The following symbols are used in this document to alert the reader to areas of potential hazard.

DANGER indicates an imminently haz-ardous situation which, if not avoided, will result in death or serious injury.

WARNING indicates a potentially haz-ardous situation which, if not avoided, could result in death or serious injury.

CAUTION identifies a hazard which could lead to damage to the machine, damage to other equipment and/or environmental pollution. Usually and instruction will be given, together with a brief explanation.

NOTE is used to highlight additional in-formation which may be helpful to you.

All wiring must be in accordance with published specifications and must be performed ONLY by qualified service personnel. Johnson Controls will not be responsible for damages/problems resulting from improper connections to the controls or application of improper control signals. Failure to follow this will void the manufacturer’s warranty and cause serious damage to prop-erty or injury to persons.

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 3

CHANGEABILITY OF THIS DOCUMENT

In complying with Johnson Controls policy for continu-ous product improvement, the information contained in this document is subject to change without notice. While Johnson Controls makes no commitment to up-date or provide current information automatically to the manual owner, that information, if applicable, can be obtained by contacting the nearest Johnson Controls service office.

It is the responsibility of operating/service personnel as to the applicability of these documents to the equipment in question. If there is any question in the mind of operating/service personnel as to the applicability of these documents, then, prior to working on the equipment, they should verify with the owner whether the equipment has been modified and if current literature is available.

TABLE OF CONTENTS Safety Symbols………………………………………………………… 2 Changeability of This Document…………………………………….. 3 Typical Installation Diagrams……..……………………………..…… 4 General Information..………………………………………………….. 6 Installation –

Pre-Installation Inspection of Equipment…………………………. 6 Rigging…………………………………………………………….... 6 Installation Site……………………………………………………… 6 Unit Mounting……………………………………………………….. 7 Separation of Units (Evaporator / Condenser)………………….. 7

Physical Data…..………………………………………………………. 9 Service Clearances and Corner Weights…………………………….12 Interconnecting Refrigerant Tubing…….....…………………………15 Outdoor Air Ductwork………………………………………………….15

Louver Sizing Guidelines…………………………………………..15 Electrical Wiring………………………………..……………………… 16

Typical Wiring Schematics………………………………...………17 Nameplate Electrical Data………………………………………... 20

Fan Performance Data……………………………………………….. 21 Motor and Drive Data……………………………………………… 23 Blower RPM Adjustment………………………………………….. 24

Low Ambient Operation / Damper Kit Installation…………………. 25 Start-Up and Operation………………………………………………. 26

Refrigerant Charges………………………………………………. 26 Pressure Switch Settings…………………………………………. 26

Microprocessor Controller……………………………………....…… 27 Operation……………………………….………………………….. 27 Safety Switches……….…………………………………………… 27 Safety Controls…………………...........………………………….. 27 Microprocessor Flash Codes…………………………………….. 27

Maintenance/Service………………………………………………… 30 Filters………………..……………………………………………… 30 Evaporator and Condenser Coils………………………............. 30 Refrigerant Circuits………………………………………………... 30 Blowers………………………………………………………………30 Drive Belts………………………………………………………….. 30

R-410A Service Procedures - Quick Reference Guide…………… 31

FORM 145.32-IOM3 (412)

4 JOHNSON CONTROLS

DSH024B-DSH060B – SINGLE COMPRESSOR UNIT – TYPICAL INSTALLATION DIAGRAM

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 5

DSH096B – DUAL COMPRESSOR UNIT – TYPICAL INSTALLATION DIAGRAM

FORM 145.32-IOM3 (412)

6 JOHNSON CONTROLS

GENERAL INFORMATION All models 2 ~ 8 tons are shipped as factory-charged unitized packages. Units can be turned on their side for short periods of time, which allows passage through standard door sizes. All unit components are securely mounted inside the heavy gauge galvanized steel cabinet. All units are lined with 1/2" thick - 2 lb density acoustical insulation to ensure the quietest operation. All models are provided with medium-efficiency 2" thick throwaway filters. All units 2 ~ 5 tons utilize a single compressor. The 8 ton model is a dual compressor unit with two independent refrigerant circuits. All units come standard with a microprocessor control board (refer to ‘Microprocessor’ section). Units will operate reliably at outdoor ambient down to 50°F. In applications requiring operation below this temperature, a low ambient damper accessory is available. The damper installs on the condenser air intake, and allows operation to 0° F ambient.

ONLY QUALIFIED PERSONNEL SHOULD PERFORM INSTALLATION AND SERVICE OF THIS EQUIPMENT.

PRE-INSTALLATION INSPECTION OF EQUIPMENT All units are factory tested to ensure safe operation and quality assembly. Units are packaged and sealed on shipping skids and shipped in first class condition. Torn and broken packaging, scratched or dented panels should be reported to carrier immediately. Internal inspection of all units should be performed prior to installation. Remove all access doors and check for visual defects that can occur during transport. Any problems found internally should be reported to carrier and manufacturer immediately. Refrigerant circuit should be checked to ensure no leaks have occurred during shipment. Install gauge set to high and low pressure ports to confirm pressure has been maintained and no leaks have occurred during shipment. Repair any damage prior to installation to ensure safe operation.

Record any unit damage on the Bill of Lading and report to carrier and factory immediately. Shipping and handling damages are not warranty items.

RIGGING PRIOR TO MOUNTING UNIT, CHECK INDIVIDUAL UNIT WEIGHTS (PAGE 10) AND VERIFY LIFTING CAPACITY OF LIFTING EQUIPMENT EXCEEDS WEIGHT OF UNITS BY SAFE MARGINS. FAILURE TO DO SO MAY RESULT IN UNIT DAMAGE, PERSONAL INJURY OR EVEN DEATH.

To ensure safe installation of the unit when ceiling mount application is specified, estimate the approximate center of gravity of the unit. The configuration of internal components for each unit is different and weight is unevenly distributed.

DETERMINE THE ACTUAL CENTER OF GRAVITY OF THE UNIT BY PERFORM-ING A TEST LIFT. LIFTING AN UNBAL-ANCED UNIT CAN CAUSE PERSONAL INJURY OR EVEN DEATH.

INSTALLATION SITE

LOCK ALL ELECTRICAL POWER SUP-PLY SWITCHES IN THE OFF POSITION BEFORE INSTALLING THE UNIT. FAIL-URE TO DISCONNECT POWER SUPPLY MAY RESULT IN ELECTRICAL SHOCK OR EVEN DEATH.

Location - To ensure unit operates at maximum efficiencies, choose a dry indoor area where the temperature is controlled between 50°F and 115°F. Consideration of surrounding areas should be taken when choosing a location to install the unit. Common vibration and sound levels associated with commercial equipment may be objectionable to people or equipment.

Failure to allow adequate space between units may result in poor unit perfor-mance and possible unit failure.

Install thermostats, air supplies and returns so that each unit will operate only on individual unit control. To assure fast drainage of condensate run-off, unit can be slightly pitched in the same direction as drain pan outlet.

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 7

UNIT MOUNTING Horizontal unit consist of an evaporator and condenser module. These two modules are rigidly attached by a joining strip across the top of the two cabinet, and two long side cross-member angles which bridge the mounting channels on the bottom of the unit. These units may be field split to allow for passage through doors, elevators, hallways, etc. Alternatively, the units may be installed as a split system after separation. Flanges for all duct connections, corner securing brackets, and refrigerant tubing couplings are shipped in the condensing section of the unit for field installation. Duct flanges for evaporator return are incorporated into the filter rack. Units may be either hung, or floor mounted. If unit is to be hung, use all mounting points indicated – regardless if unit is installed as a package or split system (refer to typical installation diagram on Page 4-5). Use of 1/2in. dia. hanger rods is recommended. Ensure the attachment point of the rods to the building structure is sufficient to support the unit weight. In order to ensure efficient condensate drainage, the unit may be pitched towards the evaporator end of the unit. A minimum of 4-in. clearance is required under the unit to allow for trapping of the evaporator condensate drain.

DSH Operating Weight (Lbs)

Unit Operating Weight (Condenser Only)

Shipping Weight (Condenser Only)

DSH024B 675 (390) 715 (430)

DSH036B 680 (400) 720 (440)

DSH048B 950 (565) 1010 (605)

DSH060B 990 (590) 1060 (630)

DSH096B 1470 (815) 1560 (855) SEPARATION OF UNITS All models are provided with refrigerant shut-off valves to allow the evaporator and condenser sections to be field split - without the necessity of reclaiming the entire unit refrigerant charge. The 8 ton model comes with self sealing brass refrigerant couplings, shown below.

The male coupling is fastened to the condenser wall via a mounting bracket. To separate the couplings, you must use a back up wrench on the female coupling to avoid stressing the refrigerant piping (see picture).

Once the couplings are unscrewed the female coupling can be gently pulled away and allowed to rest in the opening. The evaporator and condenser sections may be separated by performing the following procedures. On the 8 ton model unscrew all four couplings (pictured above) with the aid of a back-up wrench to separate the unit:

1) (2 – 5 ton models) Close all refrigerant shut-off valves, on both suction and liquid lines. Valves are not a back-seating design. Caps are wrench tight. Remove caps and turn stem clockwise to seat in the closed position.

2) (2 to 5 ton models) Use the valve access ports to reclaim the refrigerant trapped in the lines between the pairs of shut-off valves.

Use a TUBING CUTTER ONLY - do not use hacksaws to cut refrigerant tubing otherwise serious damage can occur to refrigeration system!

FORM 145.32-IOM3 (412)

8 JOHNSON CONTROLS

3) (2 – 5 ton models) Cut the refrigerant line sections between the pairs of shut-off valves. It is recommended to make this out where accessibility is greatest - in the condensing section of the unit. This will allow best access for reconnection, or attachment of an extended line set in the case of a split system.

4) Remove the interconnecting wiring between the evaporator and condenser electrical panel. Disconnect the wire terminations in the condenser electrical panel, and pull the excess wire into the evaporator panel.

5) Remove the threaded wire bushing connecting the two electrical panels

6) Remove the unit top-joining strip; Take care to remove only those screws which attach the joining strip to the evaporator and condenser cabinets.

7) Remove the two side cross-member angles. 8) Carefully pull the evaporator section away

from the condenser section. Take care not to damage the short lengths of refrigerant tubing extending into the condenser section.

The separated evaporator and condenser modules may now be individually moved to the proposed installation site for re-assembly, or separately located for split applications. Units with couplings will require a second set of matching couplings to mate with the unit coupling. These can be ordered as an accessory. The couplings must be protected for any foreign material, dust or debris if they are left uncapped for any extended period of time. When brazing couplings ensure the following is adhered to:

1) When applying paste flux to copper tube, avoid applying excessive amounts to avoid flux running inside coupling where it can cause corrosion and damage.

2) The coupling should be immersed in cold water bath, ensuring the diaphragm (threaded) is fully immersed

3) Double tipped torches are recommended to reduce brazing time. After brazing quench the couplings to reduce the temperature.

When assembling the couplings ensure the following:

1) R-410A refrigerant oil is applied to entire diaphragm surface, o-ring, and threaded male coupling end.

2) Coupling halves must be held in proper alignment with each other prior to starting the threads of the female coupling nut onto the male half. Thread by hand the first 3 rotations of the union nut. If nut does not start by hand, adjust position of the line set.

3) Using a back-up wrench tighten the female union nut until a definite increase in resistance is felt. At this point most of threads will have been covered by the nut. Ensure that the female and male bodies during any portion of the wrench installation do not rotate.

4) Make note of the location of the female nut to the bulkhead. Using a marker or scribe to mark a line lengthwise. Then finally tighten an additional one wrench flat or 60o. This final tightening is necessary to ensure a proper leak proof seal between the couplings.

Ensure evaporator motor rotation is correct upon unit start-up. Switch any two wires at contactor if blower rotation is not correct.

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 9

DSH024B & DSH036B DIMENSIONAL DATA

EVAPORATOR OPENINGS

CONDENSER OPENINGS

EVAPORATORSECTION

CONDENSER SECTION

RETURN AIR

CONDENSERINTAKE

CONDENSERDISCHARGESUPPLY

AIR

16.0

0

13.25

25.63

23.1

3

23.7

5

26.00

38.00 C.C.29.00 C.C.

58.5

0 C

.C.

61.0

0

OPTIONAL RETURN AIR (FIELD CONVERTIBLE)

OPTIONAL CONDENSER INTAKE (FIELD CONVERTIBLE)

3/4" NPT DRAINCONNECTION

2-3 TON HORIZONTAL A/C UNITDIMENSIONAL DATA

EVAPORATOR SECTIONELECTRICAL BOX ACCESS

EVAPORATORFAN ACCESS

CONDENSER FAN ACCESS

LOW VOLTAGE CONNECTION

23.75

7.18

7.00

56.0

0

71.88 C.C.

78.19

2.70

2.75

FRONT

BACK

FRONT

ELECTRICAL POWER CONNECTION

CONDENSER SECTIONELECTRICAL BOX ACCESS

COMPRESSORACCESS

EVAPORATORACCESS

2.38

1.00

NOTE: DIMENSION TOLERANCE IS 1/16"

27.5

0

4.75 17.50

7.75

14.00

6.57

FORM 145.32-IOM3 (412)

10 JOHNSON CONTROLS

DSH048B & DSH060B DIMENSIONAL DATA


4-5 TON HORIZONTAL A/C UNITDIMENSIONAL DATA

SUPPLYAIR

RETURN AIR

OPTIONAL RETURN AIR (FIELD CONVERTIBLE)

OPTIONAL CONDENSER INTAKE (FIELD CONVERTIBLE)

CONDENSERINTAKE

CONDENSERDISCHARGE

CONDENSER SECTION

EVAPORATORSECTION

35.62 C.C. 40.00 C.C.

80.50 C.C.

66.5

0 C

.C.

69.1

0

86.19

ELECTRICAL POWER CONNECTION



LOW VOLTAGE CONNECTION

CONDENSER OPENINGS

EVAPORATOR OPENINGS

FRONT

FRONT

17.50

18.5

0

15.00

16.0

0

10.12

9.73

8.13

8.75



28.00

26.7

5

29.38

23.1

3COMPRESSOR

ACCESSEVAPORATOR

ACCESS

4.75

BACK

4.25

3.00

1.00

2.38

64.0

0

3/4" NPT DRAINCONNECTION

27.50

30.5

0

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 11

DSH096B DIMENSIONAL DATA

FRONT VIEW

BACK VIEW

CONDENSERDISCHARGE

CONDENSERINTAKE

RETURN AIR

SUPPLY AIR

8 TON HORIZONTAL A/C UNITDIMENSIONAL DATA


EVAPORATORSECTION

CONDENSERSECTION

112.00

48.00 C.C. 52.00 C.C.

82.5

0

106.13

112.00

4.75 17.0025.00

21.2

510

.88

85.21

80.001.25 1.00



EVAPORATORBLOWER DRIVEACCESS PANEL

FILTER ACCESS(BOTH SIDE)

CONDENSERBLOWER DRIVEACCESS PANEL

COMPRESSORACCESS PANELCONDENSER OPENING

48.00

29.3

8

33.3

8

4.94

2.63

38.13

30.1

3

1.56

1.00

2.19

23.88

20.9

4

2.25

8.56

39.883/4" NPT DRAINCONNECTION

EVAPORATOR OPENING

EVAPORATORSECTION

CONDENSERSECTION

2.94

TOP VIEW

TX VALVE & FILTER DRIERACCESS PANEL

FORM 145.32-IOM3 (412)

12 JOHNSON CONTROLS

TYPICAL SERVICE CLEARANCES

2-5 TON HORIZONTAL A/C UNITSERVICE CLEARANCES

SUPPLYAIR

RETURN AIR CONDENSER

INTAKE

CONDENSERDISCHARGE

CONDENSER SECTION

EVAPORATORSECTION

FRONT



36 IN. MINIMUM CLEARANCE


4 IN. MINIMUM CLEARANCE(FOR DRAIN TRAP)

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 13

CONDENSERINTAKE

RETURN AIR

SUPPLY AIR

8 TON HORIZONTAL A/C UNITSERVICE CLEARANCES

EVAPORATORSECTION

CONDENSERSECTION

EVAPORATORSECTION

CONDENSERSECTION

TOP VIEW

4 IN. MINIMUM CLEARANCE(FOR DRAIN TRAP)

36 IN. MINIMUM CLEARANCE36 IN. MINIMUM

CLEARANCE


BACK VIEW

FORM 145.32-IOM3 (412)

14 JOHNSON CONTROLS

UNIT CORNER WEIGHTS

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 15

INTERCONNECTING REFRIGERANT TUBING After the evaporator and condenser sections have been mounted, the interconnecting refrigerant tubing can be fabricated. For cooling systems where the indoor and outdoor sections are installed at the same elevation, refrigerant line sizes can be usually matched with the factory supplied fittings, shown in the accompanying table below. There are exceptions for total line lengths exceeding 75 feet where pressure drop limitations are exceeded. For further information refer to JCI Application Data Sheet 247077-UAD-H-0209: “General Piping Recommendations and Refrigerant Line Length for Split-System Air Conditioners and Heat Pumps”. For following guidelines apply to field fabricated piping:

• Use hard drawn refrigeration type copper tubing where no appreciable amount of bending around pipes or obstructions is necessary. If soft copper must be used, care should be taken to avoid sharp bends which may cause a restriction. Route refrigerant tubing for minimum linear length, and minimum number of bends and fittings. Use of long radius elbows for all 90-degree bends is recommended.

• Braze all copper to copper joints with Silfos-5 or equivalent brazing material. DO NOT USE SOFT SOLDER.

• During brazing operations, flow an inert gas such as nitrogen through the system to prevent internal scaling and contamination.

Traps are not required if the piping is properly sized as they will only increase the pressure drop across the system, further reducing capacity. Once the brazing operation of refrigeration lines is completed, the field-brazed connections must be checked for leaks. Pressurize the system to a minimum of 200 psig. Use soap bubbles or alternate methods of leak-checking all field brazed joints. After completion of the leak check, evacuate the interconnecting lines to hold a 350-micron vacuum. If gauge pressure rises above 500 microns in one minute, then evacuation is incomplete or the system has a leak.

RECOMMENDED REFRIGERANT LINE SIZES

Model # LESS THAN 75 LINEAR FEET

LIQUID LINE SUCTION LINE DSH024B 3/8 3/4 DSH036B 3/8 3/4 DSH048B 1/2 7/8 DSH060B 1/2 7/8 DSH096B 2 X 1/2 2 X 7/8

DUCTWORK When installing ductwork, adhere to local Codes and sensible practice. Minimize duct runs and avoid abrupt changes in direction where possible. Allow ample access space for servicing of the coils and changing of filters. Perform regular maintenance on ducts to increase unit life, maintain efficient operation, and reduce accumulation of explosive dust. Refer to blower performance charts, and engineer duct runs and accessory pressure drop so as not to exceed maximum external static values. Louver sizing guidelines One of the key issues in obtaining optimum performance from indoor air-conditioners is the proper selection of the condenser intake and discharge louvers. Unlike outdoor air cooled units, which intake and discharge their cooling virtually unrestricted, indoor units must overcome the resistance of grilles or louvers at the outside wall - plus the restriction of any interconnecting ductwork. Our indoor air cooled air-conditioners are designed to accommodate the external static pressure loss associated with properly sized louvers of the "storm proof” type. This type of louver typically has a free area approximately 40-45% of the actual louver size. To determine the free area required for any given unit, adhere to the following guidelines:

- Size condenser air intakes for 500-750 feet/minute nominal velocity (Maximum recommended 800 feet/minute)

- Size condenser air discharge for 1,200-1,500 feet /minute nominal velocity (Maximum recommended 1,700 feet/minute)

The use of louvers with higher velocities than above may be employed, at the discretion of the engineer/installer, provided that the total air pressure drop does not exceed the capability of the condenser

FORM 145.32-IOM3 (412)

16 JOHNSON CONTROLS

fan and motor. The use of low restriction louvers with shallow blade angles can allow higher face velocities without excessive static pressure loss. Exceeding the static pressure capability of the condenser fan will result in insufficient condenser air volume. This will cause a loss in system capacity, and may cause compressor shut-down during high ambient periods. (Installation of an oversize condenser motor/drive, where applicable, may be considered in such cases.) (As a general rule, these velocities will require an intake louver sized approximately 1.25 to 1.5 times the dimensions of the duct connection on the unit, and a discharge louver sized approximately 1.5 to 2 times the duct connection dimensions.) Use only louver sections that provide different deflection angles for air discharge and air intake, to ensure the unit does not short circuit. Protect the unit from weather conditions (rain, snow) entering through the condenser air intake. All outdoor air ducts should pitch away from the unit, toward the outside wall. Connect all ducts to unit with canvas section duct connectors or choose another suitable noise and vibration absorbing device.

The Manufacturer will not accept any liability resulting from incorrect instal-lation of this equipment. Follow instal-lation instructions carefully.

ELECTRICAL WIRING Follow local electrical codes when making electrical connections. Units are completely factory wired for normal supply voltages (i.e. 208-230, 460, 575V/3Ph/60Hz) Confirm unit specifications by checking unit data plate. The factory wiring terminates in two boxes, one in each section of the unit. The electrical control boxes are located behind outer access panels. Each electrical compartment has its own control cover. Provide individual power disconnects for each unit, or each section in the case of split applications. Install a secure ground to both evaporator and condenser. If canvas flexible joints are used on ductwork, install a ground wire to the ductwork as well. Unit requires installer to provide a 24volt thermostat with appropriate heating and cooling stages as needed. The condenser section electrical cover is installed with wiring diagrams on the inner access door, which must be opened to read the diagrams

DISCONNECT AND LOCK OUT POWER WHEN SERVICING UNIT. UNIT MAY START AUTOMATICALLY IF POWER IS NOT DISCONNECTED. FAILURE TO DO SO MAY RESULT IN PERSONAL IN-JURY OR DEATH DUE TO ELECTRICAL SHOCK.

PACKAGED UNIT If unit is to be installed as a complete integral unit, the thermostat (low voltage) wiring and power wiring will be brought through the evaporator section. Check the unit nameplate for minimum circuit ampacity and fuse sizing. SPLIT SYSTEM If the unit is a split system application (condenser section remote from evaporator section), refer to the wiring diagram below.

IMPORTANT: All wiring must comply with applicable local and national codes (NEC). Type and location of disconnect switches must comply with all applicable codes.

For low voltage thermostat wiring, 18 Ga. wires may be used for up to 50 feet lengths. Low voltage runs up to 125 feet require 16 Ga. wires.

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 17

TYPICAL WIRING SCHEMATICS

FORM 145.32-IOM3 (412)

18 JOHNSON CONTROLS

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 19

FORM 145.32-IOM3 (412)

20 JOHNSON CONTROLS

ELECTRICAL DATA - STANDARD EVAPORATOR MOTOR

MODEL # VOLTAGE COMPRESSOR EVAPORATOR

FAN CONDENSER

FAN MCA MAX FUSE / CCT. BKR.

AMP QTY RLA LRA HP FLA HP FLA

DSH024B1 208-230/1/60 1 @ 12.8 58.3 0.50 4.8 0.50 4.8 25.60 35

DSH024B2 208-230/3/60 1 @ 7.7 55.4 0.50 2.5 0.50 2.5 14.63 20

DSH036B1 208-230/1/60 1 @ 16.7 79.0 0.75 6.0 0.75 6.0 32.88 45

DSH036B2 208-230/3/60 1 @ 10.4 73.0 0.75 3.6 0.75 3.6 20.20 30

DSH036B4 460/3/60 1 @ 5.8 38.0 0.75 1.5 0.75 1.5 10.25 15

DSH036B5 575/3/60 1 @ 3.8 36.5 0.75 1.2 0.75 1.2 7.15 15

DSH048B1 208-230/1/60 1 @ 21.8 107.0 0.75 6.0 1.50 9.0 42.25 60

DSH048B2 208-230/3/60 1 @ 13.1 83.1 0.75 3.6 1.50 4.5 24.48 35

DSH048B4 460/3/60 1 @ 6.1 41.0 0.75 1.5 1.50 2.2 11.33 15

DSH048B5 575/3/60 1 @ 4.4 33.0 0.75 1.2 1.50 1.8 8.50 15

DSH060B2 208-230/3/60 1 @ 16.0 110.0 1.00 3.1 1.50 4.5 27.60 40

DSH060B4 460/3/60 1 @ 7.8 52.0 1.00 1.5 1.50 2.2 13.45 20

DSH060B5 575/3/60 1 @ 5.7 38.9 1.00 1.2 1.50 1.8 10.13 15

DSH096B2 208-230/3/60 2 @ 13.1 83.1 1.50 4.5 3.00 8.5 42.48 50

DSH096B4 460/3/60 2 @ 6.1 41.0 1.50 2.2 3.00 4.2 20.13 25

DSH096B5 575/3/60 2 @ 4.4 33.0 1.50 1.8 3.00 3.4 15.10 15

ELECTRICAL DATA - OVERSIZED EVAPORATOR MOTOR

MODEL # VOLTAGE COMPRESSOR EVAPORATOR

FAN CONDENSER

FAN MCA MAX FUSE / CCT. BKR.

AMP QTY RLA LRA HP FLA HP FLA

DSH048B1 208-230/1/60 1 @ 21.8 107.0 1.00 7.4 1.50 9.0 43.65 60

DSH048B2 208-230/3/60 1 @ 13.1 83.1 1.00 3.1 1.50 4.5 23.98 35

DSH048B4 460/3/60 1 @ 6.1 41.0 1.00 1.5 1.50 2.2 11.33 15

DSH048B5 575/3/60 1 @ 4.4 33.0 1.00 1.2 1.50 1.8 8.50 15

DSH060B2 208-230/3/60 1 @ 16.0 110.0 1.50 4.5 1.50 4.5 29.00 45

DSH060B4 460/3/60 1 @ 7.8 52.0 1.50 2.2 1.50 2.2 14.15 20

DSH060B5 575/3/60 1 @ 5.7 38.9 1.50 1.8 1.50 1.8 10.73 15

DSH096B2 208-230/3/60 2 @ 13.1 83.1 2.00 5.8 3.00 8.5 43.78 50

DSH096B4 460/3/60 2 @ 6.1 41.0 2.00 2.9 3.00 4.2 20.83 25

DSH096B5 575/3/60 2 @ 4.4 33.0 2.00 2.3 3.00 3.4 15.60 20

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 21

FAN PERFORMANCE DSH024B

SUPPLY AIR BLOWER PERFORMANCE

SUPPLY CFM

AVAILABLE EXTERNAL STATIC PRESSURE - Inches W.C. ¹ 0.0 0.2 0.4 0.6 0.8 1.0

RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP

Low Static Drive3

Standard Factory Drive Hi-Static Drive

600 187 0.01 399 0.05 544 0.08 650 0.10 757 0.17 843 0.24

700 219 0.03 413 0.06 553 0.10 662 0.13 768 0.20 852 0.27

800 250 0.04 428 0.08 565 0.12 675 0.16 777 0.23 859 0.30

900 280 0.05 444 0.09 571 0.14 682 0.19 785 0.26 865 0.34

1000 312 0.06 463 0.11 585 0.16 688 0.22 790 0.29 870 0.37

1. Blower performance includes evaporator coil and 2" filters. 2. At higher evaporator airflows and wet bulb conditions, condensate carry-over may occur. Decrease airflow downward as necessary.

3. Field Supplied Low Static Drive.

CONDENSER FAN PERFORMANCE

OUTDOOR CFM

AVAILABLE EXTERNAL STATIC PRESSURE - Inches W.C.

0.0 0.2 0.4 0.6 0.8

RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP


1600 369 0.15 491 0.23 600 0.31 700 0.41 795 0.50

DSH036B


SUPPLY CFM

AVAILABLE EXTERNAL STATIC PRESSURE - Inches W.C. ¹ 0.0 0.2 0.4 0.6 0.8 1.0 1.2

RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP

Low Static Drive3


800 290 0.04 455 0.08 575 0.11 700 0.19 810 0.25 886 0.33 960 0.38

1000 362 0.08 502 0.13 617 0.19 726 0.24 820 0.31 900 0.39 980 0.47

1200 434 0.13 555 0.19 659 0.26 751 0.33 835 0.39 917 0.47 992 0.56

1400 507 0.21 613 0.28 707 0.35 792 0.43 870 0.51 943 0.59 1021 0.69

1600 572 0.25 673 0.39 759 0.48 837 0.56 911 0.65 979 0.74 ~ ~ 1. Blower performance includes evaporator coil and 2" filters.

2. At higher evaporator airflows and wet bulb conditions, condensate carry-over may occur. Decrease airflow downward as necessary.

3. Field Supplied Low Static Drive.


OUTDOOR CFM


0.0 0.2 0.4 0.6 0.8

RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP


2100 485 0.35 579 0.44 668 0.54 752 0.68 831 0.75

FORM 145.32-IOM3 (412)

22 JOHNSON CONTROLS

DSH048B SUPPLY AIR BLOWER PERFORMANCE

SUPPLY CFM

AVAILABLE EXTERNAL STATIC PRESSURE - Inches W.C. ¹ 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP

Low Static Drive3

Factory Drive + 0.75HP Hi-Static Drive + 1.0HP

1200 376 0.10 507 0.16 617 0.23 714 0.30 800 0.36 883 0.44 967 0.53 1035 0.63

1400 439 0.16 554 0.24 654 0.31 744 0.39 826 0.46 902 0.55 984 0.61 1050 0.69

1600 502 0.25 604 0.33 696 0.41 779 0.50 856 0.59 928 0.68 996 0.76 1060 0.85

1800 565 0.35 657 0.45 741 0.54 819 0.63 891 0.73 960 0.82 1024 0.93 ~ ~

2000 628 0.49 711 0.59 789 0.69 861 0.79 930 0.90 994 1.00 ~ ~ ~ ~ 1. Blower performance includes evaporator coil and 2" filters.

2. At higher evaporator airflows and wet bulb conditions, condensate carry-over may occur. Decrease airflow downward as necessary. 3. Field Supplied Low Static Drive.


OUTDOOR CFM


0.0 0.2 0.4 0.6 0.8 1.0 1.2



2500 457 0.44 536 0.56 606 0.69 671 0.81 732 0.95 789 1.08 843 1.21

DSH060B


SUPPLY CFM

AVAILABLE EXTERNAL STATIC PRESSURE - Inches W.C. ¹ 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP

Field Supplied Low Static Drive

Factory Drive + 1.0HP Hi-Static Drive +1.5HP

1600 502 0.25 604 0.33 696 0.41 779 0.50 856 0.59 928 0.68 996 0.76 1060 0.85

1800 565 0.35 657 0.45 741 0.54 819 0.63 891 0.73 960 0.82 1024 0.93 1086 1.03

2000 628 0.49 711 0.59 789 0.69 861 0.79 930 0.90 994 1.00 1056 1.10 1115 1.23

2200 690 0.65 767 0.76 839 0.88 906 0.99 971 1.10 1032 1.21 1091 1.33 1147 1.45

2400 753 0.84 824 0.96 891 1.09 954 1.21 1015 1.33 1073 1.45 ~ ~ ~ ~ 1. Blower performance includes evaporator coil and 2" filters.

2. At higher evaporator airflows and wet bulb conditions, condensate carry-over may occur. Decrease airflow downward as necessary.


OUTDOOR CFM


0.0 0.2 0.4 0.6 0.8 1.0 1.2



2900 523 0.67 595 0.81 658 0.96 717 1.10 773 1.25 826 1.40 876 1.50

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 23

MOTOR AND PULLEY DATA EVAPORATOR-STANDARD BLOWER MOTOR AND DRIVE DATA

Model Drive

Range (RPM)

Motor Adjustable Fixed

Belts Motor Pulley Blower Pulley

HP Frame Eff. Pitch Dia. Browning Pitch Dia. Browning

Rating/Size Size (%) (in) Part No. (in) Part No.

DSH024B 500-750 0.5 56 62 1.9-2.9 1VP34X5/8 6.9 AK71H A45 DSH036B 539-809 0.75 56 68 1.9-2.9 1VP34X5/8 6.4 AK66H A44 DSH048B 515-772 0.75 56 68 1.9-2.9 1VP34X5/8 6.7 AK69H 4L500 DSH060B 618-926 1 145 88.5 1.9-2.9 1VP34X7/8 5.7 AK59H A46 DSH096B 565-847 1.5 145 88.5 1.9-2.9 1VP34X7/8 6.2 AK64H A60

EVAPORATOR-OVERSIZED BLOWER MOTOR AND DRIVE DATA

Model Drive

Range (RPM)





DSH024B 704-1056 0.5 56 62 1.9-2.9 1VP34X5/8 4.9 AK51H 4L440 DSH036B 784-1176 0.75 56 68 1.9-2.9 1VP34X5/8 4.4 AK46H 4L430 DSH048B 704-1056 1 145 88.5 1.9-2.9 1VP34X7/8 4.9 AK51H A45 DSH060B 847-1173 1.5 145 88.5 2.4-3.4 1VP40X7/8 5.4 AK56H A47 DSH096B 798-1105 2 145 88.5 2.4-3.4 1VP40X7/8 5.7 AK59H A60

CONDENSER-STANDARD BLOWER MOTOR AND DRIVE DATA

Model Drive

Range (RPM)





DSH024B 397-595 0.5 56 62 1.9-2.9 1VP34X5/8 8.7 AK89H 4L540 DSH036B 448-672 0.75 56 68 1.9-2.9 1VP34X5/8 7.7 AK79H 4L520 DSH048B 516-714 1.5 145 88.5 2.4-3.4 1VP40X7/8 8.7 AK89H AX56 DSH060B 550-825 1.5 145 88.5 1.9-2.9 1VP34X7/8 6.4 AK66H AX51 DSH096B 515-686 3 184 88.5 2.8-3.8 1VP44X1 1/8 10.2 AK104H AX54

CONDENSER-OVERSIZED DRIVE DATA

Model Drive

Range (RPM)





DSH024B 539-809 0.5 56 62 1.9-2.9 1VP34X5/8 6.4 AK66H 4L500 DSH036B 585-877 0.75 56 68 1.9-2.9 1VP34X5/8 5.9 AK61H 4L490 DSH048B 556-835 1.5 145 88.5 1.9-2.9 1VP34X7/8 6.2 AK64H AX51 DSH060B 568-926 1.5 145 88.5 1.9-2.9 1VP34X7/8 5.7 AK59H AX50 DSH096B 603-805 3 184 88.5 2.8-3.8 1VP44X1 1/8 8.7 AK89H AX52

FORM 145.32-IOM3 (412)

24 JOHNSON CONTROLS

BLOWER SPEED ADJUSTMENT The RPM of the supply air and condenser air blowers will depend on the required CFM, and the static resistances of both the supply/discharge and the return/intake duct systems. With this information, the RPM for the blowers can be determined from the blower performance tables. Adjustment of blower speed is accomplished as follows: 1) Loosen belt tension by moving motor towards the blower shaft via the adjustable mounting. 2) Loosen the setscrew in the adjustable motor pulley flange. Remove external key on pulleys 4 in. diameter and

larger. 3) Slower speed will increase when moveable flange is adjusted towards the fixed flange (closed). Blower speed

will decrease when the moveable flange is adjusted away from the fixed flange (opened). Pulleys are adjustable only in half-turn increments. Do not open pulley more than five full turns for "4L" and "A" belts, or six full turns for "B" belts.

4) Once the pulley has been opened/closed the appropriate number of turns, replace the external key and

tighten the adjustment setscrew. Proper torque is 110-130 in.-lbs. 5) Install drive belt and adjust motor mount to tension belt.

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 25

LOW AMBIENT DAMPER INSTALLATION If unit operation is required at outdoor ambient below 50° F, the optional Low Ambient Damper kit should be installed to maintain acceptable condensing pressure. The damper is installed directly onto the intake duct connection as illustrated. The damper position is determined by refrigerant pressure. A direct-coupled electric damper actuator motor drives the damper open or closed, depending on the output signal from a proportional pressure control module. A pressure transducer senses the high-side refrigerant pressure, through a service access port, located on the liquid refrigerant line leaving the condenser. The pressure controller, complete with terminal connection blocks for wiring, is attached to a field-installed mounting bracket. Appropriate mounting hardware for the pressure control module and the damper actuator motor are provided with the kit. A routing hole is

provided in the condenser corner panel, near the actuator mounting location, to allow installation of the plenum-rated cable between the motor and the control module.

On dual compressor units, the actuator MUST be connected to the #1 circuit liquid line fitting. Connection to the second stage refrigerant circuit will result in system malfunction.

For detailed installation instructions, refer to the supplementary ‘Low Ambient Damper Kit’ installation instructions.

FORM 145.32-IOM3 (412)

26 JOHNSON CONTROLS

START-UP AND OPERATION Start unit and check rotation of fans and compressors. Scroll compressors will only compress in one rotational direction. Three phase compressors will rotate in either direction depending upon phasing of the power. Since there is a 50-50 chance of connecting power in such a way as to cause rotation in the reverse direction, it is important to ensure proper rotation direction is achieved when the system is installed and operated. Monitor the microprocessor board for any fault codes. This will ensure proper unit operation. Verification of proper compressor direction is made by observing that suction pressure drops and discharge pressure rises when the compressor is energized. Reverse compressor rotation also results in an elevated sound level as well as substantially reduced current draw.

There is no negative impact on durability caused by operating three phase Scroll compressors in the reversed direction for a short period of time (under one hour). However, after several minutes of operation the compressors internal protector will trip. If opposite rotation is needed, disconnect and reverse any two leads of the three phase supply. Reconnect power.

Observe unit operation and check for unusual noise or vibration.

The Air Conditioning section of this equipment is charged with R-410A; a hi-pressure refrigerant. Only qualified technicians, using appropriately pressure-rated test instruments, should perform troubleshooting or service on this equipment.

Pressure Switch Setting - All Models High Low

Cut Out (PSIG) 600 50 Cut In (PSIG) 450 75

Refrigerant Charge (LBS)

UNIT No. of Circuits Circuit 1 Circuit 2

DSH024B 1 7.30 -

DSH036B 1 8.60 -

DSH048B 1 10.50 -

DSH060B 1 11.20 -

DSH096B 2 11.40 11.65

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 27

MICROPROCESSOR CONTROLLER The microprocessor control system is specifically designed for single and dual stage air cooled systems. The control system interfaces with a conventional type thermostat. • Unit shall be complete with self-contained low-

voltage control circuit • Unit shall incorporate a lockout circuit which

provides reset capability at the space thermostat or base unit, should any of the following standard safety devices trip and shut off compressor. - Loss-of-charge/Low-pressure switch - High-pressure switch - Condensate Overflow protection switch

• Unit shall operate with conventional thermostat designs and have a low voltage terminal strip for easy hook-up.

• Unit control board shall have on-board diagnostics and fault code display.

• Standard controls shall include anti-short cycle and low voltage protection

• Control board shall monitor each compressor and refrigerant safety switch independently.

• Control board shall have random start feature • Control board shall retain last 5 fault codes in non

volatile memory which will not be lost in the event of a power loss.

OPERATION For cooling the room t-stat energizes the low-voltage circuit between “R” & “Y1”. The call is passed to the unit microprocessor control, which then determines whether the requested operation is available and, if so, which components to energize. CONTINUOUS BLOWER By setting the room t-stat fan switch set to “ON”, the supply air blower will operate continuously. With the room t-stat fan switch set to “AUTO”, the blower is energized whenever a cooling operation is requested. The blower is energized after any specified delay associated with the operation. When energized, the indoor blower has a minimum run time of 30 seconds. Additionally, the indoor blower has a delay of 10 seconds between operations.

When the room t-stat calls for cooling, the low-voltage control circuit from “R” to “Y1”and “G” is completed. The compressor and fan motor are energized. After completing the specified fan on delay for cooling, the microprocessor control will energize the blower motor. Once the room t-stat has been satisfied, it will de-energize “Y1”. If the compressor has satisfied its minimum run time, the compressor and fan de-energize. Otherwise, the unit operates the cooling system until the minimum run time for the compressor has been completed. After the compressor de-energizes, the blower is stopped following the elapse of the fan-off delay for cooling. To be available, a compressor must not be locked-out due to a high-pressure switch; low- pressure switch; condensate overflow switch; and the anti-short cycle delay (ASCD) must have elapsed. SAFETY SWITCHES Each refrigerant system is monitored to ensure it does not operate outside of its intended operating parameters. Safety switches are handled as described below. All system errors override minimum run times for compressors. High-Pressure Limit Switch If a high-pressure limit switch opens, the microprocessor control de-energizes the compressor, initiates the ASCD, and stops the fan. If a call for cooling or heating is still present at the conclusion of the ASCD, the microprocessor control will re-energize the compressor and unit fan. Should a high-pressure switch open three times within two hours of operation, the microprocessor control will permanently lock-out the compressor. The system must be manually reset by de-energizing the 24 volt power to unit, or turning the room t-stat to the “OFF” position then back to cooling position. The control will flash a fault code indicating high-pressure lock-out. Low-Pressure Limit Switch The low-pressure limit switch is not monitored during the initial 30 seconds of compressor operation. After the initial 30 seconds have passed, the microprocessor control will monitor the low-pressure switch for another 30 seconds. If the low-pressure switch fails to close after the 30 second monitoring phase, the microprocessor control will de-energize the compressor, initiate the ASCD, and stop the fan. Once the low-pressure switch has been proven (closed during the 30-second monitoring period as described above), the microprocessor control board will continue to monitor the low-pressure limit switch for any openings. If the low-pressure switch opens for

FORM 145.32-IOM3 (412)

28 JOHNSON CONTROLS

greater than 5 seconds, the microprocessor control board will de-energize the compressor, initiate the ASCD, and stop the fan. If the call for cooling is still present at the conclusion of the ASCD, the microprocessor control will re-energize the compressor. Should a low-pressure switch fault three (3) times within one (1) hour of operation, the microprocessor control board will lock-out the compressor and flash a fault code indicating a low-pressure lock-out. Condensate Overflow Switch A Condensate Overflow fault occurs when the Condensate Overflow switch opens for more than two line cycles. The compressor is shutdown regardless of Minimum Run Time, ASCD is initiated, and alarm is tripped. The fan continues operating in its current state. Compressor will re-energize once the Condensate Overflow switch closes, and ASCD has been satisfied and a call for cooling is still present. The microprocessor control board logs the first incident per compressor request. If the compressor request is removed, the fault occurrence counter is reset to zero. Should the Condensate Overflow switch open three within two hours of run time, the microprocessor control board will lock-out the compressor, turn off the fan and flash a fault code indicating a Condensate Overflow lock-out. SAFETY CONTROLS The microprocessor control monitors the following inputs: 1. A High-Pressure Switch on each compressor

circuit to protect against excessive discharge pressures.

2. A Low-Pressure Switch on each compressor circuit to protect against loss of refrigerant charge.

3. A Condensate Overflow Switch to protect against condensate overflow.

Compressor Protection In addition to the external pressure switches, the compressor also has inherent (internal) protection. If there is an abnormal temperature rise in a compressor, the internal protection will immediately shut down the compressor. The microprocessor control incorporates features to minimize compressor wear and damage. An anti-short cycle delay (ASCD) is utilized to prevent short cycling of the compressor. Additionally, a minimum run time is imposed any time a compressor is energized. The ASCD is initiated on unit start-up and on any compressor reset or lockout.

Microprocessor Control Unit Flash Codes Various flash codes are utilized by the microprocessor control to aid in troubleshooting. Flash codes are distinguished by the short on and off cycle used (approximately 200ms on and 200ms off). To show normal operation, the control boards flash a 1 second on, 1 second off “heart beat” during normal operation. This is to verify that the microprocessor is functioning correctly. Do not confuse this with an error flash code. To avoid confusion the 1-flash, fault code is not used.

FORM 145.32-IOM3 (412)

JOHNSON CONTROLS 29

Current alarms or active restrictions are flashed on the microprocessor control LED. 1. LAST ERROR – When this button is pressed and

released, it flashes the last five (5) flash codes on the board’s LED. The most recent alarm is shown first and the oldest alarm is shown last.

2. TEST RESET – When this button is pressed and released, any anti-short cycle delays (ASCD) are bypassed for one cycle. When pressed twice, any active lockouts are reset.

3. COMM SETUP – If the board is to be networked. with other units, this button is used to set the network address. Press the button once and it scans the bus, then assigns itself the first available address, (starts at 2). It then flashes that address one time. Pressing the button twice causes the control to flash the address.

FLASH CODES Description

On Steady This is Control Failure 2 Flashes Control waiting ASCD (Anti-Short Cycle Delay) * 3 Flashes High Pressure Compressor 1 Lockout 4 Flashes High Pressure Compressor 2 Lockout 5 Flashes Low Pressure Compressor 1 Lockout 6 Flashes Low Pressure Compressor 2 Lockout 7 Flashes Condensate Overflow Switch Lockout

11 Flashes Compressor(s) locked out due to Economizer running (Free Cooling) * 13 Flashes Compressor Held Off due to Low Voltage 14 Flashes EEPROM Storage Failure

OFF No Power or Control Failure

Note: Flash rates marked with * are NOT alarms.

FORM 145.32-IOM3 (412)

30 JOHNSON CONTROLS

MAINTENANCE / SERVICE DISCONNECT AND LOCK OUT POWER WHEN SERVICING UNIT. FAILURE TO DO SO MAY RESULT IN PERSONAL IN-JURY OR DEATH DUE TO ELECTRICAL SHOCK. Exercise care when working around the sharp metal edges of door panels or door frames, etc. These edges can cause injury.

EVAPORATOR AND CONDENSER COILS Inspect the evaporator coil at filter change intervals. Inspect the condenser coil at least semi-annually. A dirty condenser coil will result in elevated condensing pressures and poor unit performance. Dirty or clogged evaporator coils causes low suction pressure and lost capacity. If the coils appear dirty, they should be cleaned using a mild detergent or a commercial coil cleaning agent. REFRIGERANT CIRCUIT(S)- With the unit operating, check and record the compressor discharge and suction pressures. The compressor running current should also be recorded. A maintenance log of these readings can indicate if the unit is operating within its normal limits. Abnormal readings should be investigated, and the Cause corrected. BLOWERS - Inspect both the evaporator and condenser blowers at each regular service interval. Clean blower wheels as needed. Bearings are permanently sealed ball type,

and do not require lubrication. Check bearings for any signs of wear (movement between inner and outer races). Ensure bearing locking collars are secure to the shaft, and that collar locking screw is properly set. Check that the blower wheel is tight on the shaft, and that the hub set screws are tightened to the proper torque. DRIVE BELTS - Examine belts periodically for wear. Glazed areas on the drive surfaces indicate overheating due to belt slippage. Ideal tension is the lowest tension at which the belt will not slip under peak load conditions. Over-tensioning shortens belt and bearing life (see section ‘Blower Speed Adjustment’). The tension on the belt should be adjusted for a deflection of 1/64 of an inch per inch of belt span, with the appropriate force applied at the midpoint of the span. Tension “New” belts at the maximum value indicated. Used belts should be maintained at the minimum value. FILTERS - Inspect filters monthly and replace as necessary. Use UL Class 2 rated filters. Factory supplied filters are medium efficiency, extended surface pleated type. Replacements should be of the same type, to maintain optimum airflow performance. Filter sizes are as follows:

FILTERS

Unit Model Qty - Size DSH024B 2 - 25x14x2 DSH036B 2 - 25x14x2 DSH048B 2 - 25x16x2 DSH060B 2 - 25x16x2 DSH096B 4 - 20x16x2

LD13547 BELT TENSION ADJUSTMENT DEFLECTION FORCE VERSUS DRIVE BELT CROSS-SECTION

FORM 145.35-IOM3 (412)

JOHNSON CONTROLS 31

R-410A QUICK REFERENCE GUIDE

Refer to Installation Instructions for specific installation requirements.

• R-410A Refrigerant operates at 50 - 70 percent higher pressures than R-22. Be sure that servicing equipment and replacement components are designed to operate with R-410A.

• R-410A Refrigerant cylinders are rose colored. • Recovery cylinder service pressure rating must be 400 psig. DOT 4BA400 or DOT BW400. • Recovery equipment must be rated for R-410A. • Do not use R-410A service equipment on R-22 systems. All hoses, gages, recovery cylinders, charging

cylinders and recovery equipment must be dedicated for use on R-410A systems only. • Manifold sets must be at least 700 psig high side, and 180 psig low side, with 550 psig retard. • All hoses must have a service pressure rating of 800 psig. • Leak detectors, must be designed to detect HFC refrigerants. • Systems must be charged with refrigerant. Use a commercial type metering device in the manifold

hose. • R-410A can only be used with POE type oils. • POE type oils rapidly absorb moisture from the atmosphere. • Vacuum pumps will not remove moisture from POE type oils. • Do not use liquid line driers with a rated working pressure rating less than 600 psig. • Do not install suction line driers in the liquid line. • A liquid line drier is required on every unit. • Do not use an R-22 TXV. If a TXV is to be used, it must be an R-410A TXV. • Never open system to atmosphere when under vacuum. • If system must be opened for service, evacuate system then break the vacuum with dry nitrogen and

replace filter driers.

Subject to change without notice. Printed in U.S.A. Copyright© 2012 by Unitary Products Group. All rights reserved. Form 145.32-IOM3 (412)

Engineered Systems P.O. Box 1592 York Products York, PA PA Group 17405 17405

model dsh horizontal r-410a supersedes: 145.32-iom2 (908...

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