Page 34
PROBLEM 6: CONTROL SIGNALS LOW FLAME SENSE DURING HEATING MODE
Condition
Possible Cause
Corrective Action/Comments
6.0
− Unit operates correctly but the
diagnostic lights flash low flame
sense code
6.1.1
Sensor rod is improperly located on
the burner.
ACTION 1 −
Check the sensor rod for proper
location on the burner. Properly locate the sen-
sor rod or replace if rod cannot be located cor-
rectly.
sense code.
LED#1−Slow Flash
LED#2−Fast Flash
6.1.2
Sensor rod is contaminated.
ACTION 1 −
Check sensor rod for contamination
or coated surface. Clean the sensor rod with
steel wool or replace sensor. DO NOT USE
SAND PAPER TO CLEAN ROD. SAND PAPER
WILL CONTRIBUTE TO THE CONTAMI-
NATION PROBLEM.
PROBLEM 7: INDOOR BLOWER FAILS TO OPERATE IN COOLING, HEATING, OR CONTINUOUS
FAN MODE
Condition
Possible Cause
Corrective Action/Comments
7.0
− Indoor blower fails to operate in
continuous fan, cooling, or heating
mode.
7.1.1
Miswiring of furnace or improper con-
nections at control or indoor blower
motor.
ACTION 1−
Correct wiring and/or replace any
loose connections. Check for correct wiring and
loose connections.
7.1.2
120V is not being supplied to the in-
door air blower or blower motor fail-
ure.
ACTION 1 −
Check for 120V at the various calls
for indoor blower by energizing "Y", "G", and "W"
individually on the low voltage terminal strip.
Note that when "W’ is energized, the blower is
delayed 45 seconds. If there is 120V to each mo-
tor tap but the blower does not operate, replace
the motor.
7.1.3
Defective control board
ACTION 1 −
If there is not 120V when "Y", "G", or
"W" is energized, replace the control.
7.1.4
Defective run capacitor
ACTION 1 −
Replace capacitor
PROBLEM 8: RF STATIC DURING TIME FOR IGNITION
Condition
Possible Cause
Corrective Action/Comments
8.0
− AM radio interference.
8.1.2
Ignitor operation
ACTION 1 −
Call Technical Support, Dallas.
