IF AND CHECK or REPAIR
Induced blower does
not energize
3 Flash code does not come on
1. Induced blower wiring.
2. Induced blower.
Induced blower does
not energize
3 Flash code does come on
1. Pressure switch stuck closed.
2. Pressure switch is mis-wired or jumpered.
Induced blower is
energized
2 Flash code does not come o n
Wait for the pre-purge to expire.
2 Flash code
comes on
Induced blower turns off
1. Pressure switch stuck in the open position.
2. Pressure switch, tubing and wiring.
3. Obstruction in furnace venting that is preventing proper combustion airflow.
Pre-purge time h as
expired
HSI element does not glow r ed
within 10 seconds.
1. Broken or damaged HSI element.
2. Broken or damaged HSI element leadwires.
HSI element i s glow-
ing red.
No other visible control system
action
Wait for HSI element warm up time to expire.
HSI element warm u p
time has expired a nd
main valve has been
energized.
Main valve does not light within
trial for ignition period
1. Induced blower moving main burner gas away from the HSI element.
2. Inlet gas pressure too low for main burner ignition.
3. Input line voltage too low to heat HSI element.
4. HSI element incorrectly positioned.
5. Clogged or incorrect main burner orifice.
Main burner lights
within trial for ignition
period.
Main valve i s de-energized a t the
end of the trial for ignition period.
If main flame i s not sensed during
trial for ignition, system will shut o ff
HSI element and main gas flow,
then g o through another purge
period and initiate another ignition
trial. A total o f 4 ignition trials will
be attempted before the system
goes into lockout.
1.
Line voltage to L1 terminal of integrated furnace control must be
120 volts with reference to furncace chassis.
2. Furnace must be reliably connected to earth ground.
3. Induced blower moving main burner flame away from the flame sensor rod.
4. Inlet gas pressure too low for proper flame sensing.
5. Flame sensor rod contaminated or in incorrect position.
Main burner stays o n
after the end of t he
trial for ignition p e-
riod.
Circulating fan is not turned on after
30-second time delay.
1. Wiring between system control and integrated furnace control.
Proper operation of integrated furnace control.
Main burner goes o ut
before thermostat call
for heat ends.
4 Flash code comes on
1.
2.
Open high limit switch.
High limit wiring in good condition and securely connected.
Main burner goes o ut
before thermostat call
for heat ends.
4 Flash code does not come on
Green LED off
1.
Induced blower moving main burner flame away from flame sensor rod.
3.
Pressure switch has opened.
1.
2.
Open flame rollout switch
Rollout switch wiring in good condition
Broken or damaged blower
4.
Flame sensor rod ceramic or leadwire overheated.
Gas supply / flow reduced or interrupted.
5 Flash code comes
on.
TABLE 10 : GENERAL TROUBLESHOOTING INTEGRATED FAN CONTROL
42
3.
2.
2.