Tempstar A Series, Installation, Start-Up, Operating, Service And Maintenance Instructions

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F96CTN and G96CTN (Series A): Installation, Start-up, Operating, Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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2. Wait until the blower off delay is completed.
3. Turn 115 VAC power off.
4. Check the position of setup switch SW1-4. When set to OFF,
airflow is raised 7% for low Heat, and 10% for high heat. Factory
default position is ON.
5. Turn 115 VAC power on.
6. Re-check high heat temperature rise.
After the temperature rise has been verified:
1. Remove jumpers from thermostat terminals.
2. Allow the blower off delay to complete.
3. Turn set-up switches SW1-2 to the OFF position unless two-stage
thermostat operation is desired. See Fig. 38 .
4. Proceed to “Adjust Blower Off Delay” or install blower door if
complete.
Adjust Blower Off Delay (Heat Mode)
1. Remove blower door if installed.
2. Turn Dip switch SW-7 or SW-8 ON or OFF for desired blower off
delay. See Table 19 and Fig. 38 , Fig. 60 and Fig. 73 .
Table 19 – Blower Off Delay Setup Switch
Adjust Cooling Airflow – High-Speed and
Low-Speed Cooling
The ECM blower can be adjusted for a range of airflows for low-speed
or high-speed cooling. See Table 17 – Air Delivery – CFM (With Filter)
and Fig. 60 – Furnace Setup Switches and Descriptions. Depending on
the model size, the cooling airflow can be adjusted from 1.5 to 6 tons
based on 350 per CFM ton.
NOTE: 6 ton airflow will truncate at 2200 CFM on applicable models.
The high-speed or single-speed cooling airflow is adjusted by turning
Setup switches SW2-1, SW2-2 and SW2-3 either ON or OFF. Select the
required airflow from Table 17 . Table 17 is based upon 350 CFM per
ton. For other CFM per ton Setup switch selections, see Fig. 38 , 61 and
74.
The Continuous Fan airflow selection via Setup switches SW3 is also the
switch setting for low-speed cooling when the furnace is used with a
2-speed cooling or heat pump unit. Adjust the Continuous Fan CFM
Setup switches SW3 to match the airflow required for low-speed
cooling. Select the required airflow from Table 17 and Fig. 60 .
NOTE: The airflow selected via SW3 (Low-Speed Cooling Airflow)
cannot exceed the airflow selected via SW2 (High-Speed Cooling
Airflow). For other CFM per ton Setup switch selections, see Fig. 38 and
61.
NOTE: The cooling airflow settings for SW2 and SW3 selections are
the same, EXCEPT for the default values. See Table 17 .
For a complete explanation of cooling airflow, refer to the section titled
“Sequence of Operation.”
Adjust Continuous Fan Airflow (and Low-Speed
Cooling Airflow)
Adjust continuous fan and low-stage cooling airflow using SW3 and
refer to Fig. 60 and Table 17 . The continuous fan speed can be further
adjusted at a conventional thermostat using the continuous fan speed
select function. Changing the continuous fan speed at a conventional
thermostat DOES NOT change the low-speed cooling airflow selected
via SW3 at the control board. Refer to the section titled “continuous
Blower Speed selection for Thermostat.”
Adjust Thermostat Heat Anticipator.
1. Mechanical thermostat. Set thermostat heat anticipator to match the
amp. draw of the electrical components in the R-W/W1 circuit.
Accurate amp. draw readings can be obtained at the wires normally
connected to thermostat subbase terminals, R and W. The
thermostat anticipator should NOT be in the circuit while
measuring current.
a. Set SW1-2 switch on furnace control board to ON.
b. Remove thermostat from subbase or from wall.
c. Connect an amp. meter as shown in Fig. 65 across the R and W
subbase terminals or R and W wires at wall.
d. Record amp. draw across terminals when furnace is in low heat
and after blower starts.
e. Set heat anticipator on thermostat per thermostat instructions and
install on subbase or wall.
f. Turn SW1-2 switch OFF.
g. Install blower door.
2. Electronic thermostat: Set cycle rate for 3 cycles per hr.
A96316
Fig. 65 – Amp. Draw Check with Ammeter
Check Safety Controls
The flame sensor, gas valve, and pressure switch were all checked in the
Start-up procedure section as part of normal operation.
1. Check Main Limit Switch
This control shuts off combustion system and energizes
air-circulating blower motor, if furnace overheats. By using this
method to check limit control, it can be established that limit is
functioning properly and will operate if there is a restricted
return-air supply or motor failure. If limit control does not function
during this test, cause must be determined and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or sheet
metal until the limit trips.
c. Unblock return air to permit normal circulation.
d. Burners will re-light when furnace cools down.
2. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.
a. Turn off 115-v power to furnace.
b. Disconnect inducer motor lead wires from wire harness.
c. Turn on 115-v power to furnace.
d. Set thermostat to “call for heat” and wait 1 minute. When
pressure switch is functioning properly, hot surface igniter
DESIRED HEATING MODE
BLOWER OFF DELAY (SEC.)
SETUP SWITCH
(SW1-7 AND -8)
POSITION
SW1-7 SW1-8
90 OFF OFF
120 ON OFF
150 OFF ON
180 ON ON R Y W G
10 TURNS
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)
HOOK-AROUND
AMMETER
EXAMPLE:
5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
=
0.5 AMPS FOR THERMOSTAT
ANTICIPATOR SETTING
FROM UNIT 24-V
CONTROL TERMINALS