Johnson Controls TM9T*MP Adjustment of Temperature Rise, Adjustment of FAN Control Settings

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505309-UIM-D-0511

MANIFOLD PRESSURE “U” TUBE CONNECTION

 

OUTLET

 

 

PRESSURE TAP

 

GAS VALVE

1/4” TUBING

 

 

 

 

FLAME

 

 

MAINIFOLD

 

 

PIPE

SENSOR

 

 

 

 

 

 

3.5 IN

 

 

 

WATER

 

 

 

COLUMN

GAS

 

 

GAS

 

U-TUBE

PRESSURE

BURNERS

 

 

MANOMETER

SHOWN

 

 

FIGURE 41: Reading Gas Pressure

ADJUSTMENT OF TEMPERATURE RISE

DANGER

The temperature rise, or temperature difference between the return air and the supply (heated) air from the furnace, must be within the range shown on the furnace rating plate and within the application limitations shown in Table 7.

The supply air temperature cannot exceed the “Maximum Supply Air Temperature” specified in these instructions and on the furnace rating plate. Under NO circumstances can the furnace be allowed to operate above the Maximum Supply Air Temperature. Operating the furnace above the Maximum Supply Air Temperature will cause pre- mature heat exchanger failure, high levels of Carbon Monoxide, a fire hazard, personal injury, property damage, and/or death.

After about 5 minutes of operation, determine the furnace temperature rise. Take readings of both the return air and the heated air in the ducts, about six feet (1.83 m) from the furnace where they will not be affected by radiant heat. Increase the blower speed to decrease the temperature rise; decrease the blower speed to increase the rise.

All direct-drive blowers have multi-speed motors. The blower motor speed taps are located on the furnace control board in the blower com- partment. Refer to Figure 41, and the unit-wiring label to change the blower speed. To use the same speed tap for heating and cooling, the heat terminal and cool terminal must be connected using a jumper wire and connected to the desired motor lead. Place all unused motor leads on Park terminals. Two park terminals are provided.

Do not energize more than one motor speed at a time or damage to the motor will result.

ADJUSTMENT OF FAN CONTROL SETTINGS

This furnace is equipped with a time-on/time-off heating fan control. The fan on delay is fixed at 30 seconds. The fan off delay has 4 settings (60, 90, 120 and 180 seconds). The fan off delay is factory set to 120 sec- onds. The fan-off setting must be long enough to adequately cool the furnace, but not so long that cold air is blown into the heated space. The fan-off timing may be adjusted by positioning the jumper on two of the four pins as shown in Figure 41.

CONTINUOUS FAN

BLOWER OFFSPEED JUMPER

DELAY JUMPER

DIAGNOSTIC ERROR CODE

RETRIEVAL BUTTON

HUMIDIFIER

TERMINAL

ELECTRONIC AIR

CLEANER TERMINAL

FIGURE 42: Furnace Control Board

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Johnson Controls Unitary Products

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Contents Models TM9T*MP List of SectionsList of Figures List of TablesSafety Requirements Section I SafetySpecific Safety Rules and Precautions Combustion AIR Quality List of Contaminants Codes and StandardsInspection Furnace Location and ClearancesFloor Base and Ductwork Installation Downflow Section II DuctworkDuctwork General Information Duct FlangesCoil Installation COIL/FURNACE Assembly MC/FC/PC Series CoilsFurnace Assembly MC & FC Series Coils Coil Flange InstallationCoil / Furnace Assembly HC Series Coils Downflow Duct ConnectorsBottom Return and Attic Installations Critical Coil ProjectionAttic Installation Suspended Furnace / Crawl Space InstallationHorizontal Application Downflow ApplicationSide Return Filter InstallationSection III Filters GAS Safety GAS Piping InstallationSection IV GAS Piping Horizontal FiltersSection V Electrical Power High Altitude Pressure Switch ConversionElectrical Power Connections GAS Orifice Conversion for Propane LPLOW Voltage Control Wiring Connections Supply Voltage ConnectionsTwo Stage Air Conditioner Two Stage PSC Furnace PP32U70124 DN22H00124 DP22U70124TWO Stage PSC Furnace OD Models Section VI Twinning Twinning Instructions Twinning OperationCondensate Drain Location Condensate hoses must slope downwards at all pointsCondensate Drain Termination Typical. Combustion Pipe Drain TeeWill cause the furnace Airflow Horizontal Left Right Configuration Johnson ControlsCombustion AIR and Vent Safety Section Viii Combustion AIR and Vent SystemCombustion AIR/VENT Pipe Sizing Model Input Pipe Size MaximumCombustion AIR and Vent Piping Assembly Elbow a DimensionCombustion AIR / Venting Fitting Equivalent LengthVent Clearances Home LayoutVenting Multiple Units Vent SystemVent Applications and Termination Downward Venting Outdoor Combustion AirCombustion AIR Supply Ambient Combustion Air SupplyCombustion Air Source From Outdoors Dampers, Louvers and Grilles Canada OnlyAir Supply Openings and Ducts Free AreaSpecially Engineered Installations Ventilated Combustion AirVentilated Combustion Air Termination Vent Blower Rotation Section IX START-UP Adjustments GAS Piping Leak Check Calculating the Furnace Input NAT. GAS Ignition System SequenceRevolution Cu Ft Seconds ForRead the manifold gas pressure Adjustment of Manifold GAS Pressure & Input RateRead the inlet gas pressure Adjustment of Temperature Rise Adjustment of FAN Control SettingsLeft Side Airflow Data Scfm Blower Performance CFM Any Position without filterBottom Airflow Data Scfm Section X Safety Controls Section XI Normal Operation and DiagnosticsFurnace Control Diagnostics Fabricated Parts Section XII Replacement Parts ListDiagnostic Fault Code Storage and Retrieval Section Xiii Wiring Diagram Wiring DiagramJohnson Controls Unitary Products York Drive Norman, OK
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