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368261-UIM-B-1008

12

Johnson Controls Unitary Products

Annual Fuel Utilization Efficiency (AFUE) numbers are determined in accordance with DOE Test procedures.
Wire size and over current protection must comply with the National Electrical Code (NFPA-70-latest edition) and all local codes.

SUPPLY VOLTAGE CONNECTIONS

1.

Provide a power supply separate from all other circuits. Install
overcurrent protection and disconnect switch per local/national
electrical codes. The switch should be close to the unit for conve-
nience in servicing. With the disconnect or fused switch in the OFF
position, check all wiring against the unit wiring label. Refer to the
wiring diagram in this instruction.

2.

Remove the screws retaining the wiring box cover. Route the
power wiring through the opening in the unit into the junction box
with a conduit connector or other proper connection. In the junc-
tion box there will be 3 wires, a Black Wire, a White Wire. Connect
the power supply as shown on the unit-wiring label on the inside of
the blower compartment door or the wiring schematic in this sec-
tion. The black furnace lead must be connected to the L1 (hot)
wire from the power supply. The white furnace screw must be con-
nected to neutral. Connect the power supply ground to the green
screw (equipment ground) An alternate wiring method is to use a
field provided 2” (5.1 cm) x 4” (10.2 cm) box and cover on the out-
side of the furnace. Route the furnace leads into the box using a
protective bushing where the wires pass through the furnace
panel. After making the wiring connections replace the wiring box
cover and screws. Refer to Figure 18.

3.

The furnace's control system requires correct polarity of the power
supply and a proper ground connection. Refer to Figure 18.

LOW VOLTAGE CONTROL WIRING CONNECTIONS

Install the field-supplied thermostat by following the instructions that
come with the thermostat. With the thermostat set in the OFF position
and the main electrical source disconnected, connect the thermostat
wiring from the wiring connections on the thermostat to the terminal
board on the ignition module, as shown in Figures 19-24, Thermostat
Charts. Electronic thermostats may require the common wire to be con-
nected as shown in Figure 16. Apply strain relief to thermostat wires
passing through cabinet. 

The 24-volt, 40 VA transformer is sized for the furnace components
only, and should not be connected to power auxiliary devices such as
humidifiers, air cleaners, etc. The transformer may provide power for an
air conditioning unit contactor.

AIR CONDITIONER CONNECTIONS

This furnace may be used with single-stage or two-stage air condition-
ing units.

For Single-Stage A/C -

 Connect the low voltage wiring as shown in

Figure 19, Thermostat Chart.

For Two-Stage A/C - 

Use a two-stage thermostat, connect the low volt-

age wiring as shown in Figure 20, Thermostat Chart.

For Two-Stage A/C using a Single-Stage Thermostat - 

connect the

low voltage wiring as shown in Figure 20, Thermostat Chart.

This furnace control board can control a two-stage A/C using only a sin-
gle-stage thermostat. In this case, the furnace control switches between
high cool and low cool based on the calculated cooling load.

Table 6: 

Ratings & Physical / Electrical Data

Input

Max/Min

Output

Max/Min

Nominal

Airflow

Air Temp. Rise

Max Input

Air Temp. Rise

Min Input

MBH

kW

MBH

kW

CFM

m

3

/min

°F

°C

°F

°C

60/30

17.6/8.8

47/24

13.8/7.0

1200

34.0

35-65

19-36

20-50

11-28

80/40

23.5/11.8

62/32

18.2/9.4

1200

34.0

40-70

22-39

20-50

11-28

80/40

23.5/11.8

62/32

18.2/9.4

1600

45.3

40-70

22-39

20-50

11-28

100/50

29.3/14.7

78/40

22.8/11.7

1600

45.3

40-70

22-39

20-50

11-28

100/50

29.3/14.7

78/40

22.8/11.7

2000

56.6

35-65

19-36

20-50

11-28

120/60

33.7/16.9

95/48

27.8/14.1

2000

56.6

45-75

25-42

25-55

13-31

Max. Outlet

Air Temp

Blower 

Blower

Wheel

size

AFUE

%

Max 

Over-Current 

Protect

Total Unit

Amps

Min. wire Size 

(awg) @ 75 ft 

one way

°F

°C

HP

Amps

165

73.9

1/3

4.8

11 x 8

80.0

15

7.0

14

170

76.7

1/3

4.8

11 x 8

80.0

15

7.5

14

170

76.7

1/2

7.5

11 x 10

80.0

15

10.0

14

170

76.7

1/2

7.5

11 x 10

80.0

15

10.0

14

165

73.9

1

14.5

11 x 11

80.0

20

17.0

12

175

79.4

1

14.5

11 x 11

80.0

20

17.0

12

 FIGURE 18:  

Electrical Wiring

The power connection leads and wiring box may be relocated to the
left side of the furnace. Remove the screws and cut wire tie holding
excess wiring. Reposition on the left side of the furnace and fasten
using holes provided.

Electrical Entry

Junction
Box

L1-Hot

Neutral

Connect ground
lead to screw

BLK

WHT

Set the heat anticipator in the room thermostat to 0.1 amps. Setting
it lower will cause short cycles. Setting it higher will cause the room
temperature to exceed the set points.

Some electronic thermostats do not have adjustable heat anticipa-
tors. They should be set to six cycles per hour. Follow the thermo-
stat manufacturer's instructions.

Summary of Contents for CM8M*MP

Page 1: ...Outside and Ambient Combustion Air 21 Gas Valve 25 Furnace Control Board 26 Wiring Diagram 30 LIST OF TABLES Unit Clearances to Combustibles 4 Coil Projection Dimensions PC Series Coils 8 Cabinet and...

Page 2: ...ting point provided that the tubes are lifted at the front of the heat exchangers where attached to the vestibule panel Do not use the top return bend of the heat exchangers as lifting points as the t...

Page 3: ...the National Fire Protection Association Inc Batterymarch Park Quincy MA 02269 or for only the NFGC contact the American Gas Association 400 N Capital N W Washington DC 20001 or www NFPA org CANADA NS...

Page 4: ...ng but not limited to decks and porches the following require ments shall be satisfied 1 INSTALLATION OF CARBON MONOXIDE DETECTORS At the time of installation of the side wall horizontal vented gas fu...

Page 5: ...es are rotated down for shipment In order to use the flanges remove the screw holding an individual flange rotate the flange so it is in the upward position and reinstall the screw then repeat this fo...

Page 6: ...igure 4 When moving or handling this furnace prior to installation always leave the doors on the furnace to provide support and to prevent damage or warping of the cabinet When lifting the furnace sup...

Page 7: ...te the vent blower 90 left or right so that the vent pipe passes through the side of the furnace casing rather than the end See Figure 6 COIL INSTALLATION COIL FURNACE ASSEMBLY MC FC PC SERIES COILS F...

Page 8: ...e furnace and coil casing and seal appropriately NOTE Dimension C should be at least 2 3 of dimension D See Fig ure 12 CRITICAL COIL PROJECTION The coil assembly must be located in the duct such that...

Page 9: ...24 25 29 5 For Cladded door add appoximately an additional 75 28 5 Electrical Entry Gas Pipe Entry Thermostat Wiring FRONT 14 1 1 5 23 SUPPLY END C 24 38 20 5 B Gas Pipe Entry Thermostat Wiring 33 A...

Page 10: ...as piping may be connected from either side of the furnace using any of the gas pipe entry on both sides of the furnace Refer to Figure 14 All filters and mounting provision must be field supplied All...

Page 11: ...he input rate back up to approxi mately 76 000 BTU H which is what it should be for that furnace at 6 000 feet SECTION V ELECTRICAL POWER ELECTRICAL POWER CONNECTIONS Field wiring to the unit must be...

Page 12: ...4 volt 40 VA transformer is sized for the furnace components only and should not be connected to power auxiliary devices such as humidifiers air cleaners etc The transformer may provide power for an a...

Page 13: ...tric heat on thermostat is not necessary C 24 Volt Common Y Compressor SINGLE STAGE AIR CONDITIONER Y Compressor Contactor SINGLE STAGE AIR CONDITIONER C 24 Volt Common R 24 Volt Hot Y1 Single Stage C...

Page 14: ...sed with batteries Thermostat Installer Setup 0170 System Type must be set to 8 2 Heat 2 Cool Multistage Conventional Connection of the C terminal 24 volt common is optional when used with batteries T...

Page 15: ...t Y1 Single Stage Compressor MODULATING FURNACE CONTROL G Fan MODULATING FURNACE Y Y2 Second or Full Stage Compressor DHUM Dehumidification Open on Humidity Rise W Modulating Heat Part Numbers SAP Leg...

Page 16: ...unction Light W Auxiliary Heat SINGLE STAGE HEAT PUMP 1 1 Part Number S1 2HU16700124 3 Y2 Second Stage Compressor Step 9 of Thermostat Installer Configuration Menu must be set to Pump OFF Step 1 of Th...

Page 17: ...2 OUT Second Stage Heat Y2 OUT Second Stage Compressor Y1 Single Stage Compressor X L Malfunction Light Y2 Second Stage Compressor W Auxiliary Heat BS Bonnet Sensor BSG Bonnet Sensor YORKGUARD VI CONT...

Page 18: ...at R 24 Volt Hot Heat XFMR RC 24 Volt Hot Cool XFMR AUX Auxiliary Heat Step 1 of Thermostat Installer Configuration Menu must be set to HP2 Selection of GAS ELEC switch on thermostat not necessary The...

Page 19: ...nal is removed 3 Hot Heat Pump The hot heat pump feature will work when the control is wired to a 2 stage thermostat and a 2 stage heat pump 4 Hot Heat Pump The hot heat pump feature will not work whe...

Page 20: ...have no dimen sion smaller than 0 25 0 64 cm 3 A manually operated damper or manually adjustable louvers are not permitted for use 4 A automatically operated damper or automatically adjustable lou ve...

Page 21: ...ional area as the free area of the air supply inlet opening to which it connects 4 The blocking effects of louvers grilles and screens must be given consideration in calculating free area If the free...

Page 22: ...ollowing steps shall be followed for each appliance connected to the venting system being placed into operation while all other appliances connected to the venting system are not in operation 1 Inspec...

Page 23: ...per input rate using natu ral gas with a heating value of 1030 BTU Ft3 38 4 MJ m3 If the heat ing value of your gas is significantly different it may be necessary to replace the orifices NOTE DO NOT s...

Page 24: ...300 750 78 46 92 231 25 144 288 720 80 45 90 225 26 138 277 692 82 44 88 220 27 133 267 667 84 43 86 214 28 129 257 643 86 42 84 209 29 124 248 621 88 41 82 205 30 120 240 600 90 40 80 200 31 116 232...

Page 25: ...urnace temperature rise Take temperature readings of both the return air and the heated air in the ducts about six feet away from the furnace where they will not be affected by radiant heat Increase o...

Page 26: ...removed Electrical supply to this unit is dependent upon the panel that covers the blower compartment being in place and properly positioned ROLLOUT SWITCH CONTROLS These controls are mounted on the...

Page 27: ...l senses that flame is present the circulating blower starts at low speed 5 The furnace fires at 70 of full rate for 30 45 seconds then drops to the minimum 50 firing rate 6 The firing rate is automat...

Page 28: ...not connected properly check for loose plug or loose wires in plug Steady On Red Control fault has been detected or there is 24 volts present without 115 volts Check that there is 24 volts and 115 vol...

Page 29: ...L Models Only MISCELLANEOUS ORIFICE BURNER Natural 45 SIGHT GLASS OVAL 2 Req d GASKET FOAM Door 1 5 ft req d GASKET INTAKE PAN PLUG VENT HOLE BRACKET DOOR WIRING HARNESS FERRULE 3 Req d GROMMET 3 Req...

Page 30: ...nted in U S A 368261 UIM B 1008 Copyright 2008 by Johnson Controls Inc All rights reserved Supersedes 368261 UIM A 0508 Johnson Controls Unitary Products 5005 York Drive Norman OK 73069 SECTION XI WIR...

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