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349215-JIM-B-1008

Johnson Controls Unitary Products

29

NOTE: All entry holes should be field sealed to prevent rain 

water entry into the building.

FIGURE 13 - FRONT VIEW DIMENSIONS 15, 17.5, 20 & 25 TON

UTILITIES ENTRY DATA

HOLE

OPENING SIZE 

(DIA.)

USED FOR

A

1-1/8” KO

Control Wiring

Side

3/4” NPS (Fem.)

Bottom

B

3-5/8” KO

Power Wiring

Side

3” NPS (Fem.)

Bottom

C

2-3/8” KO

Gas Piping (Front)

1

1.

One-inch gas piping NPT required.

D

1-11/16” Hole

Gas Piping (Bottom)

1,  2

 

2.

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

11-1/2

(A) CONTROL WIRING

ENTRY

COIL

GUARD 

KIT

CONDENSER

COILS

(B) POWER 

WIRING

ENTRY

5

9-3/4

21.00

6-3/8

7-1/8

35

5-7/8

136-1/4

GAS OR ELECTRIC
HEAT
ACCESS

DOT PLUG

(For pressure

drop reading)

BLOWER 

COMPARTMENT

ACCESS

(Auxiliary)

(C) GAS 

SUPPLY

ENTRY

CONTROL BOX

ACCESS

VENT AIR

OUTLET 

HOODS

BLOWER MOTOR
ACCESS (Location
of Optional VFD Bypass)

BLOWER ACCESS
(Location of
Optional VFD)

52-5/8

180-19/32

COMPRESSOR ACCESS

DISCONNECT

SWITCH 

LOCATION

ECONOMIZER / MOTORIZED DAMPER

FIXED OUTDOOR INTAKE AIR AND

POWER EXHAUST RAIN HOODS

(See detail Y)

92

46-5/8

35-1/4

33

2-3/4

3-3/4

(B) POWER WIRING

ENTRY

BOTTOM SUPPLY

AND RETURN

AIR OPENINGS

   (See Note)

(A) CONTROL WIRING

ENTRY

21-1/2

11-1/8

(D)

GAS SUPPLY

ENTRY

UNIT BASE RAILS
Shown separately to illustrate

RETURN

AIR

Bottom Duct openings.  Power 
and Gas Piping Connection
location.

NOTE:
For curb mounted units, refer to the curb hanger
dimensions of the curb for proper size of the 
supply and return air duct connections.

12-1/2

9-1/4

8-1/8

46-5/8

9-3/4

COMBUSTION

AIR INLET HOOD

SUPPLY 

AIR

Summary of Contents for 20 Series

Page 1: ...URE 6 INSTALLATION 7 OPERATION 45 START UP COOLING 53 START UP GAS HEAT 53 TROUBLESHOOTING 56 See the following page for a complete Table of Contents NOTES CAUTIONS AND WARNINGS The installer should p...

Page 2: ...STATIC PRESSURE AND POWER ALTITUDE AND TEMPERATURE CORRECTIONS 32 PHASING 44 CHECKING SUPPLY AIR CFM 44 AIR BALANCE 44 OPERATION 45 SEQUENCE OF OPERATIONS OVERVIEW 45 COOLING SEQUENCE OF OPERATION 45...

Page 3: ...VALVE AND CONTROLS 52 25 TYPICAL GAS VALVES 54 26 PROPER FLAME ADJUSTMENT 55 27 TYPICAL FLAME APPEARANCE 55 28 UNIT CONTROL BOARD 65 LIST OF TABLES Tbl Pg 1 UNIT APPLICATION DATA 8 2 CONTROL WIRE SIZE...

Page 4: ...e personnel should install repair main tain or service this equipment Observe all precautions in the literature on labels and tags accompanying the equipment whenever working on air conditioning equip...

Page 5: ...ould pay particular attention to the words NOTE CAUTION and WARNING Notes are intended to clarify or make the installation easier Cau tions are given to prevent equipment damage Warn ings are given to...

Page 6: ...ies 20 Model Number Nomenclature ZZ If desired option combination is not listed above ZZ will be assigned and configuration options will be located in digits 15 18 A No Options Installed Installation...

Page 7: ...lectrical Code C22 1 Current Gas Installation Codes CSA B149 1 Local plumbing and waste water codes Other applicable local codes Refer to the Unit Application Data table and to the Gas Heat Applicatio...

Page 8: ...nit is to be installed on a roof curb or special frame other than a Unitary Products roof curb gasketing must be applied to all surfaces that come in contact with the unit underside TABLE 1 UNIT APPLI...

Page 9: ...provisions for ade quate combustion and ventilation air in accordance with Section 5 3 Air for Combustion and Ventilation of the National Fuel Gas Code ANSI Z223 1 in U S A or Sections 7 2 7 3 or 7 4...

Page 10: ...ange surfaces on the hood prior to installing the hood Extend gasketing 1 4 inch beyond the top and bottom of the two side flanges to insure adequate sealing Adjusting the damper to the desired air fl...

Page 11: ...porator coil and must be kept clean or replaced with same size and type Dirty filters will reduce the capacity of the unit and will result in frosted coils or safety shutdown Minimum filter area and r...

Page 12: ...2 p r o v i d e a r e l a y o u tp u t to c l o s e th e o u td o o r e c o n o m i z e r d a m p e r s w h e n th e th e r m o s ta t s w i tc h e s to th e s e t b a c k p o s i ti o n 2 4 V o l t T...

Page 13: ...Can ada and or local codes Refer to the Dimensions Figure 13 for installation location If any of the wire sup plied with the unit must be replaced replacement wire must be of the type shown on the wi...

Page 14: ...All units require a one inch pipe connection at the entrance fitting Maximum capacity of pipe in cubic feet of gas per hour Based upon a pressure drop of 0 3 inch water column and 0 6 specific gravity...

Page 15: ...of the gas lines external to the unit have been purged of air 5 The gas supply should be a separate line and installed in accordance with all safety codes as prescribed under Limitations After the ga...

Page 16: ...gas as it will quickly dissolve white lead or most standard commercial compounds Shellac base compounds such as Rectorseal 5 are satisfactory for this type of gas Check all connections for leaks when...

Page 17: ...ze and de energize terminals R to G MINIMUM POSITION ADJUSTMENT With thermostat set to indoor fan on position or termi nals R to G energized turn the Minimum Position Adjusting screw located on the da...

Page 18: ...vert this pressure measure ment to a proportional 0 5 VDC electrical output Pressure transmitting plastic tubing 1 4 diameter must be field supplied and installed from the transducer to both the ductw...

Page 19: ...h limit set point is adjustable between 0 WC and 5 WC with the factory default setting of 4 5 WC If the duct static pressure reaches the high limit set point then the supply fan motor will be shutdown...

Page 20: ...imum clearances to allow for adequate internal cooling of the drive during operation The unit comes with a mounting bracket installed in the Blower Access compartment which may accommodate other vendo...

Page 21: ...ng pressure modulating bypass control valve installed on the system 1 discharge line is used to divert high tem perature high pressure refrigerant around the TXV in order to maintain a desired minimum...

Page 22: ...T T1 AQ1 AQ SO SO SR SR A B C D TR TR1 24 Vac HOT 24 Vac COM EF EF1 2 3 4 5 1 Exhaust Air Adjustment Screw Exhaust Air LED Damper Min Position Screw Indoor Air Quality Max Adjustment Screw Indoor Air...

Page 23: ...J18DJ Elec 2728 476 888 888 476 J20DJ Elec 2760 481 899 899 481 J25DJ Elec 2846 496 927 927 496 Unit Size Total Shipping Weight 6 Point Loads lbs A B C D E F J15DJ Gas 2660 302 316 453 590 565 434 J18...

Page 24: ...E REFRIGERANT 22 Lb Oz SYSTEM No 1 23 0 24 0 23 8 23 8 SYSTEM No 2 23 8 24 0 23 8 23 8 OPERATING WEIGHTS LBS BASIC UNIT COOLING ONLY 2260 2540 2560 2660 GAS ELECTRIC N24 2460 2740 2760 2860 N32 2500 2...

Page 25: ...100 1 1 7 2 0 0 None 0 0 36 1 45 E18 18 0 1 21 7 36 1 45 E36 36 0 2 43 3 63 1 70 E54 54 0 2 65 0 74 0 90 E72 72 0 2 86 6 95 6 110 575 8 3 78 0 9 5 9 0 0 None 0 0 28 2 35 E18 18 0 1 17 3 29 0 35 E36 3...

Page 26: ...80 1 5 8 2 0 0 None 0 0 44 6 50 E18 18 0 1 17 3 44 6 50 E36 36 0 2 34 6 53 6 60 E54 54 0 2 52 0 62 2 70 E72 72 0 2 69 3 79 5 90 J25 25 208 47 1 245 3 7 38 6 0 0 None 0 0 159 4 200 E18 13 5 1 37 5 159...

Page 27: ...100 1 1 7 2 5 0 None 0 0 41 1 50 E18 18 0 1 21 7 42 3 50 E36 36 0 2 43 3 69 4 70 E54 54 0 2 65 0 80 2 90 E72 72 0 2 86 6 101 9 110 575 8 3 78 0 9 5 9 4 0 None 0 0 32 2 40 E18 18 0 1 17 3 34 0 40 E36...

Page 28: ...80 1 5 8 2 4 0 None 0 0 48 6 60 E18 18 0 1 17 3 48 6 60 E36 36 0 2 34 6 58 6 60 E54 54 0 2 52 0 67 2 70 E72 72 0 2 69 3 84 5 90 J25 25 208 47 1 245 3 7 38 6 10 0 None 0 0 169 4 200 E18 13 5 1 37 5 16...

Page 29: ...T ACCESS DOT PLUG For pressure drop reading BLOWER COMPARTMENT ACCESS Auxiliary C GAS SUPPLY ENTRY CONTROL BOX ACCESS VENT AIR OUTLET HOODS BLOWER MOTOR ACCESS Location of Optional VFD Bypass BLOWER A...

Page 30: ...wer 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 supp...

Page 31: ...ES LOCATION CLEARANCE Front 36 Rear 24 Less Economizer 49 With Economizer Left Side Filter Access 24 Less Economizer 36 With Economizer 3 Right Side Cond Coil 36 Below Unit1 1 Units may be installed o...

Page 32: ...the static pressure and BHP Since no temperature data is given we will assume an air temperature of 70 F Table 11 shows the correction factor to be 0 832 Corrected static pressure 1 5 x 0 832 1 248 I...

Page 33: ...349215 JIM B 1008 Johnson Controls Unitary Products 33 FIGURE 16 ALTITUDE TEMPERATURE CONVERSION FACTOR...

Page 34: ...0 0 9 5 2 4 7 0 7 5 7 5 1 208 VOLT AND HIGH STATIC DRIVE 965 6 0 1 2 2 9 2 6 1 0 3 6 3 2 0 8 4 0 3 6 0 5 4 7 4 2 0 4 5 0 4 4 980 5 5 1 3 3 0 2 7 1 1 3 7 3 3 0 9 4 1 3 7 0 6 4 8 4 3 0 5 5 1 4 6 1025 4...

Page 35: ...4 5 9 5 0 980 5 0 1 6 5 3 4 5 1 4 5 8 4 9 1 2 6 3 5 3 0 7 6 9 5 8 1010 4 0 1 8 5 8 4 9 1 7 6 3 5 3 1 5 6 9 5 8 1 0 7 5 6 3 1020 3 5 1 9 6 1 5 1 1 8 6 5 5 5 1 6 7 1 6 0 1 1 7 8 6 6 1035 3 0 2 0 6 2 5...

Page 36: ...9 1 2 6 3 5 3 0 7 6 9 5 8 0 2 7 3 6 1 1010 4 0 1 8 5 8 4 9 1 7 6 3 5 3 1 5 6 9 5 8 1 0 7 5 6 3 0 5 7 9 6 7 1020 3 5 1 9 6 1 5 1 1 8 6 5 5 5 1 6 7 1 6 0 1 1 7 8 6 6 0 6 8 3 7 0 1035 3 0 2 0 6 2 5 2 1 9...

Page 37: ...8 3 4 1 0 4 4 3 9 0 8 5 0 4 5 0 6 5 6 5 0 208 VOLT AND HIGH STATIC DRIVE 965 6 0 1 2 2 7 2 5 0 9 3 2 2 9 0 6 3 7 3 3 0 4 4 4 3 9 0 2 5 0 4 5 980 5 5 1 3 2 9 2 6 1 0 3 4 3 0 0 7 3 8 3 4 0 5 4 5 4 0 0 3...

Page 38: ...5 1 0 2 6 9 5 8 980 5 0 1 9 4 5 3 8 1 5 5 4 4 5 1 0 6 3 5 3 0 4 7 2 6 1 995 4 5 2 1 4 5 3 9 1 6 5 5 4 7 1 1 6 4 5 4 0 5 7 5 6 3 1025 3 5 2 3 4 9 4 1 1 8 5 8 4 9 1 3 6 7 5 7 0 7 8 0 6 7 1050 2 5 2 5 5...

Page 39: ...980 5 0 1 9 4 5 3 8 1 5 5 4 4 5 1 0 6 3 5 3 0 4 7 2 6 1 0 1 8 5 7 1 995 4 5 2 1 4 5 3 9 1 6 5 5 4 7 1 1 6 4 5 4 0 5 7 5 6 3 0 2 8 6 7 3 1025 3 5 2 3 4 9 4 1 1 8 5 8 4 9 1 3 6 7 5 7 0 7 8 0 6 7 1050 2...

Page 40: ...9 7 0 3 13 7 11 2 1215 4 0 2 7 8 6 7 0 2 1 10 4 8 5 1 4 12 3 10 1 0 6 14 3 11 7 1255 3 0 3 0 9 1 7 4 2 4 11 0 9 0 1 7 12 9 10 6 0 9 15 0 12 3 1290 2 0 3 2 9 5 7 8 2 7 11 5 9 4 2 0 13 5 11 1 1 2 15 6...

Page 41: ...er performance table TABLE 20 POWER EXHAUST PERFORMANCE MOTOR SPEED STATIC RESISTANCE OF RETURN DUCTWORK IWG 0 2 0 3 0 4 0 5 0 6 CFM KW CFM KW CFM KW CFM KW CFM KW HIGH 5250 0 83 4500 0 85 4200 0 88 3...

Page 42: ...e TXV s left to the factory setting If the TXV s have been adjusted in the field The charging chart may no longer apply FIGURE 18 CHARGING CHART 17 5 TON 17 5 Ton Charging Chart 100 150 200 250 300 35...

Page 43: ...with the TXV s left to the factory setting If the TXV s have been adjusted in the field the charging chart may no longer apply FIGURE 20 CHARGING CHART 25 TON 25 Ton Charging Chart 100 150 200 250 30...

Page 44: ...d 20 ton units and Model 1LD0435 for 25 ton units Refer to the Blower Motor and Drive Data Table 21 Note the following 1 The supply air CFM must be within the limitations shown in the Unit Application...

Page 45: ...ESSORS BEFORE TAKING ANY TEST MEASURE MENTS TO ASSURE A DRY INDOOR COIL OPERATION SEQUENCE OF OPERATIONS OVERVIEW For these units the thermostat makes a circuit between R and Y1 for the first stage of...

Page 46: ...cool ing the low voltage control circuit from R to G and Y1 is completed The UCB energizes the blower motor if the fan switch on the room thermostat is set in the AUTO position and drives the economi...

Page 47: ...nt plus 5 F free cooling is available If free cooling is available with a Y1 call then the con trol modulates the economizer dampers to maintain the First Stage SAT Control setpoint plus or minus one...

Page 48: ...ree times within two hours of operation the UCB will lock out the associated compres sor and flash a code Table 27 If the other compressor is inactive the condenser fans will be de energized LOW AMBIE...

Page 49: ...blower motor If the second stage of heat is required heater con tactor 7M will be energized Note that on the 54 KW 240V heater heater contactors 7M 8M will be energized and on the 72 KW 240V heater he...

Page 50: ...t motor control The draft motor control contacts close and start the draft motor As the speed of the draft motor reaches approximately 2500 RPM the cen trifugal switch contact located on the end of th...

Page 51: ...shut down until the specified fan off delay for heating has been satisfied The UCB will de energize the blower motor When the thermostat calls for the first stage of heating the low voltage control c...

Page 52: ...open It will continue to try and ignite the pilot for a maximum of 85 seconds then if the pilot flame is not detected the ignition control will lock out furnace operation until 24V power is removed fr...

Page 53: ...Measure evaporator fan motor s amp draw 8 Set the room thermostat fan switch to off 9 Turn unit electrical power off OPERATING INSTRUCTIONS 1 Turn unit electrical power on 2 Set the room thermostat se...

Page 54: ...as well as the supply piping 2 Check for correct manifold gas pressures See Checking Gas Input page 55 3 Check the supply gas pressure It must be within the limits shown on rating nameplate Supply pr...

Page 55: ...t gas valve and downstream from the main manual shut off valve 3 Remove the gas piping closure panel 4 Disconnect wiring to the gas valves and spark ignit ors Remove the manifold burner gas valve asse...

Page 56: ...GUIDE On calls for cooling if the compressors are operating but the supply air blower motor does not energize after a short delay the room thermostat fan switch is in the AUTO position 1 Turn the the...

Page 57: ...at to the UCB 9 If 24 volts is present at the room thermostat but not at the UCB check for proper wiring between the thermostat and the UCB i e that the thermostat G terminal is connected to the G ter...

Page 58: ...mper in the Mate N Lock plug and in the wiring from the Mate N Lock plug to the Y1 ECON terminal 13 For units with economizers If 24 volts is present at the Y1 OUT terminal check for 24 volts at the Y...

Page 59: ...tween the LPS2 terminals 9 If 24 volts is present at the UCB Y2 terminal and none of the protection switches have opened the UCB may have locked out the compressor for repeat trips The UCB should be f...

Page 60: ...h the last five alarms on the LED If the compressor is locked out remove any call for cooling This will reset any compressor lock outs NOTE While the above step will reset any lock outs compressor 2 w...

Page 61: ...h VFD check that line voltage is being supplied to the M3 Auxiliary contacts Check for loose wiring between the contactor and the supply air blower motor 3 If M3 is pulled in and voltage is supplied a...

Page 62: ...m thermostat for contact between R and G during W1 calls On calls for heating the supply air blower operates but the draft motor does not the room thermostat fan switch is in the AUTO position 1 The d...

Page 63: ...d remove the pilot orifice from the pilot burner The orifice is removed in the direction opposite the flow of gas Inspect the orifice for obstruction If it is clear replace the main gas valve The igni...

Page 64: ...me cases it may be necessary to zero the ASCD for the compressors in order to perform trouble shooting To reset all ASCDs for one cycle press and release the UCB TEST RESET button once Flash codes tha...

Page 65: ...onds the display will revert to its normal display exiting the Option Setup mode When saving the control board only saves the parameters for the currently dis played mode Option Byte or Heat Delay HEA...

Page 66: ...fusion a 1 flash flash code is not used TABLE 28 HEAT DELAY Heat Fan On Delay Heat Fan Off Delay Red LED 8 Red LED 4 Red LED 2 Red LED 1 60 180 On On On On 60 90 On On On Off 60 60 On On Off On 60 30...

Page 67: ...349215 JIM B 1008 Johnson Controls Unitary Products 67...

Page 68: ...change without notice Printed in U S A 349215 JIM B 1008 Copyright 2008 by Johnson Controls Inc All rights reserved Supersedes 349215 JIM A 1007 Johnson Controls Unitary Products 5005 York Drive Norma...

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