Instructions / Assembly

Troubleshooting
Care – 45
SYMPTOM POSSIBLE CAUSE CORRECTIVE ACTION
4. Burner comes "ON",
blower comes "ON",
but cycles "ON"
and "OFF" while
burner remains "ON".
A. Furnace not operating at
full rate.
Check for low gas pressure at gas valve - should be 4" W.C. for Natural Gas, 11" W.C.
for L.P. Gas. Check burner orifice.
5. Burner comes "ON",
blower comes "ON",
but burner cycles
"OFF" and "ON" with
blower "ON".
A. Furnace operating over-
rate.
Check for high gas pressure at the gas valve - correct if necessary. See correct
pressure above.
B. Line voltage too low. Check line voltage to motor, if below 115 volts the motor will run too slow.
C. Recirculation.
Heated air discharging against an object causing recirculation, such as a hall
installation or a large piece of furniture within 4' of discharge.
6. Furnace operates but
turns "OFF" before
room temperature is
attained.
A. Thermostat location.
Check location of the thermostat. It should not be in the path of warm air discharge
from the furnace, near a lamp, or above a TV set or stereo.
B. Defective thermostat. Check the thermostat calibration or replace.
7. Furnace operates but
will not shut "OFF"
when room
temperature is
attained.
A. Thermostat wiring
defective.
Check the thermostat wiring from furnace to the thermostat - may be shorted together
by a nail or staple.
B. Thermostat location.
Check thermostat location - if on an outside wall or there is a hole in wall behind the
thermostat causing cold air to contact the thermostat, relocate the thermostat.
8. Abnormal operation.
A. Blower noise.
Check the motor mounts - they may be loose. Fan blade could be out of balance. Set
screw may be loose on the motor shaft. Blower may be rubbing on the fan shroud.
Motor may need oiling. Correct as needed.
B. Expansion noise ticking.
Check installation - casing may be twisted or not level when installed. Expansion slip
joint may be binding; check by removing vent cap assembly from outside wall.
C. Selector switch defective
(2-speed).
During normal furnace operation the motor will be on "LOW" speed when operating on
minimum input capacity and on "HIGH" speed when operating at maximum input
capacity. If there is no change in motor speed, replace the selector switch.
9. Burner comes “ON”
but goes “OFF” after
operating for no
apparent reason.
A. Vent tube and air inlet
tube improperly
installed.
Check the vent tube and air inlet tube. Follow the installation instructions. Be sure
joints are tight and both tubes are in place. Use only the vent tubes furnished. Do not
extend tubes beyond their original length.