Operating instructions

Table 17--Troubleshooting Guide-Heating
SYMPTOM CAUSE REMEDY
Water in gas line Drain. Install drip htg.
No power to f_mace Check power supply fuses, widng, or circuitbreaker,
Check transformer,
No 24-v power supply to control circuit NOTE: Some transformers have internal overcurrerd
protection that requires a ccol_lown period to reset.
Miswirod or loose connections Check all widng and wirenut connections
Burned-out heat anticipator in Replace thermostat.
Burners will not ignite, thermostat
Broken thermostat wire Run continuity check, Replace wire if necessary.
Check flame ignition and sense electrode positioning.
Mlaaligned spark electrodes Adjust as necessary.
1.Check gas line for air. Purge as necessary.
NOTE: After purging gas line of air, wait at least 5 minutes for any
No gas at main burners gas to dissipate before attempting to light unit.
2. Check gas valve.
Dirty air filter Clean or replace filter as necessary.
Check gas pressure at manifold match with that on
Gas input to fumace too low unit nameplate.
Unit undersized for application Replace with proper unit or add additional unit.
inadequate heaUng. Restricted airflow Clean or replace rifler. Remove any restriction.
Use faster speed tap if available, or install aflemate
Blower speed too low motor.
Check rotation of blower, thermostat heat anticipator settings,
Limit switch cycles main burners temperature rise of unit. Adjust as necessary.
1.Tighten all screws around burner compartment.
Incomplete combustion results in: 2. Cracked heat exchanger. Replace.
Poor flame characteristics. Aldehyde odors, carbon monoxide, sooting 3. Unit oven3red. Reduce input (change orifices or
flame, floating flame adjust gas line or manifold pressure).
4. Check burner alignment,
Table 18---Troubleshooting Guide-LED Error Codes
SYMPTOM CAUSE REMEDY
Check 5-amp fuse on IGC*, power to unit, 24-v circuit breaker, and
Hardware failure, transformer. Units without a 24-v circuit breaker have an internal
(LED OFF) Loss of power to control module (IGC)'. overload in the 24-v transformer. If the ovedoad tdps, ariow 10 min-
utes
for automatic reset.
High limit switch opens during heat
exchanger warm-up period before fan-on Ensure unit is fired on rate; ensure temperature rise is correct.
Fan ON/OFF delay modified delay expires.
{LED/FLASH) Limit switch opens within three minutes Ensure unWs exfamai static pressure is within application guidelines.
after blower_ff delay timing in Heating mode.
Draft switch faults. Check the operation of the indoor (evaporator) fan motor. Ensure
(LED 2 flashes) High tempemtore limit switch is open. that the supply-air temperature rise is in accordance with the range
on the unit nameplate.
Flame sense fault. The IGC* sensed flame that should not be
(LED 3 flashes) present. Reset unit. If problem persists, replace central board.
4 consecutive limit switch faults. Check operation of indoor (evaporator) fan motor and that supply-air
(LED 4 flashes) Inadequate airflow to unit temperature rise agrees with range on unfl nameplate information.
Ignition lockout. Unit unsuccessfully attempted ignition for Check ignitor and flame sensor electrode spacing, gaps, etc. Ensure
(LED 5 flashes) 15 minutes, that flame sense and ignflion wires are properly terminated. Verify
that unit is obtaining proper amount of gas.
Check for proper voltage. If motor is operating, check the speed
sensor plug/IGC Terminal J2 connection. Proper connection:
Induced-draft motor fault. IGC does not sense that ioduced-draft PIN 1 White
(LED 6 flashes) motor is operating.* PIN 2 -- Red
PIN 3 -- Black.
Roliout switch will automatic.aflyreset, but IGC* will continue to iock-
Roflout switch fault, out unit. Check gas valve operation. Ensure that induced-draft
(LED 7 flashes) Roltout switch has opened, blower wheel is properly secured to motor shaft. Reset unit at unit
disconnect.
Rofiout control fault. Microprocessor has sensed an error in the if error code is not cleared by resetting unit power, replace the IGC*.
(LED 8 flashes) software or hardware.
Temporary software lock out. Electrical interference Reset 24-v. to control board or tom thermostat off,
then on again. Fault will automatically
(LED 9 flashes) impeding IGC software reset itsefl in one (1) hour.
* WARNING i_. : If the IGC must be replaced, be sure to ground yourself to dissipate any electrical charge that may be present before handling new control board. The
IGC is sens"I_ to static electflaity and may he damaged if the necessary precautions are not taken.
IMPORTANT: Refer to Table 17--Troubleshoofing Guide-q-leating for additional troubleshooting analysis.
LEGEND
tP=re----_tegrated Gas Unit Controller
LED -- Light*Emfltiog Diode
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