Shut Down; Sequence Of Operation; Heating; Fan On - Whirlpool WFAU Installation Instructions Manual

Adjust Blower Speed
WARNING
Electrical Shock Hazard
Disconnect power before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical shock.
NOTE:
See the wiring diagrams in the "Troubleshooting" section
while performing the following procedure.
If the construction will continue or the furnace will not be used for
a period of time, follow the shut down procedure.
1. Set the thermostat to the lowest setting.
2. Disconnect power.
During a call for heat, the thermostat closes R - W circuit of the
control board. The control board verifies limit switches are closed
and pressure switch is open. The induced draft blower relay
closes, causing the blower to run. As vent pressure is developed
by the induced draft blower, the pressure switch closes. After a
15-second pre-purge, the control energizes the hot surface
igniter. After the 7-second warm-up time, the control energizes
the main gas control valve, causing the main burners to ignite.
The hot surface igniter is de-energized 3 seconds after the main
valve opens.
During a fan on call, the thermostat energizes the R - G circuit of
the control board, immediately causing the fan to energize the
COOL speed. The fan remains energized as long as the
thermostat calls for fan on operation.
If a call for cooling is energized during a fan on call, the fan
continues to operate at the COOL speed. If a call for heat is
energized during a fan on call, the control de-energizes the fan
immediately and begins the heat call/ignition sequence.

Shut Down

SEQUENCE OF OPERATION

Heating

Fan On

1. Disconnect power.
2. For heating speed, check the temperature rise and make the
necessary adjustments to the blower speed tap. See the
wiring diagrams in the "Troubleshooting" section.
3. Reconnect power.
4. Recheck the temperature rise. Repeat the procedure as
necessary to achieve optimum temperature rise.
5. If the furnace does not begin to heat the room, see the
"Troubleshooting" section.
3. Remove burner access panel.
4. Turn off the gas supply at the manual gas shutoff valve.
5. Replace the burner access panel.
If flame is sensed during this time, the main valve remains
energized and the control starts the 30-second heat blower "on"
delay.
As heating demand is met, the thermostat de-energizes the R - W
circuit. The control de-energizes the main valve, causing the
burners to shut off. The induced draft blower shuts off after a
15-second post-purge delay. The circulating air blower will
continue to operate until the user-selectable heat blower "off"
delay expires. The control returns to standby mode once the heat
blower "off" delay expires.
At the end of the fan on call, the thermostat de-energizes the R -
G circuit of the control, causing the fan to be de-energized
immediately.
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