17
24 volts supplied to gas valve during ignition but no
main gas flow
1. Gas valve may be defective. Replace if necessary.
2. Gas piping may be plugged. Check for adequate gas
supply to gas valve at union.
Burner operates, insufficient heat
1. Check the thermostat for proper setting and location.
The thermostat should not be located where it will be
affected by another heat source. (Lamps, ovens,
sunlight, etc.)
2. Check for clean air filters and proper air flow.
3. Check burner for proper gas firing rate.
4. Be sure unit is not undersized for its thermal load.
5. Check thermostat anticipator. (0.9 amps)
Burner does not shut off
Note:
Burner will stop when the door switch is open. With
the door open, secure the door switch in the closed position
by depressing the switch. The means for securing the door
switch must be removed once this testing has been com-
pleted.
1. Disconnect the thermostat wires from TT connections
on the burner junction box. If the burner shuts off, check
for:
a. Short circuit in the thermostat wires.
b. Defective thermostat.
Burner flame without motor running
Gas valve is stuck in open position - Replace the control,
burner and heat exchanger may need cleaning.
Noisy fire
Readjust combustion air to reduce volume of air being drawn
into the burner. (Caution: See burner adjustment)
High Gas Bills
1. Check the combustion air adjustment.
2. Be sure the proper size orifice is being used.
3. Be sure the return air filter is clean.
4. Be sure the home is insulated, windows and doors fit
tightly, and there are no air leaks in the heating ducts.
5. Check room thermostat to be sure the setting is not
higher than necessary. Low humidity requires higher
temperatures for comfort. Perhaps humidity should be
increased.
Circulation blower will not operate even though the
burner operates
1. Turn on the manual blower switch. If the blower operates,
check the fan switch.
2. Check the wiring to the motor.
3. Check for a burned out motor.
