Carrier 48JCH 04-06 Series Service And Maintenance Instructions page 31

FLASH
SYMPTOM
CODE
c,d
ON Normal Operation
OFF No Power or Hardware Failure
1 Flash Check Fuse, Low Voltage Circuit Fuse is blown or missing, or
2 Flashes Limit Switch Fault
3 Flashes Flame is Sense Fault
4 Flashes Four Consecutive Limit Switch
Faults
5 Flashes Ignition Lockout Fault
6 Flashes Pressure Switch Fault
7 Flashes Burner Thermal Switch Fault
8 Flashes Internal Control Fault
NOTE(S):
a. Alarm codes on the IGC will be lost if power to the unit is interrupted.
b. If the pressure switch is stuck closed on a W1 call, then the unit will sit idle and do nothing with no fault on the IGC.
c. There is a 3-second pause between alarm code displays.
d. If more than one alarm code exists, all applicable alarm codes will be displayed in numerical sequence.
LEGEND
IGC — Integrated Gas Unit Control
LED — Light-Emitting Diode
Table 9 — IGC Board LED Alarm Codes
CAUSE
—
Loss of power to control module
(IGC)
short circuit in secondary
(24 VAC) wiring.
High temperature limit switch is
open.
The IGC sensed flame that
should not be present.
Inadequate airflow to unit.
Unit unsuccessfully attempted
ignition for 4 times.
Open pressure switch.
Burner thermal switch is open
Microprocessor has sensed an
error in the software or hardware.
31
a,b
REMEDY
Check 5-amp fuse on the IGC, power to unit, 24V circuit breaker,
and transformer. Units without a 24V circuit breaker have an
internal overload in the 24V transformer. If the overload trips, allow
10 minutes for automatic reset.
Replace fuse if needed. Verify no short circuit in low voltage
(24 VAC) wiring.
Check the operation of the indoor (evaporator) fan motor.
Ensure that the supply-air temperature rise is in accordance with
the range on the unit nameplate.
Clean or replace filters.
Reset unit. If problem persists, replace the IGC board.
Check the operation of the indoor (evaporator) fan motor and that
supply-air temperature rise agrees with range on the unit nameplate
information.
Check igniter and flame sensor electrode spacing, gaps, etc.
Ensure that flame sense and ignition wires are properly terminated.
Verify that unit is obtaining proper amount of gas.
Verify wiring connections to pressure switch and inducer motor.
Verify pressure switch hose is tightly connected to both inducer
housing and pressure switch.
Verify inducer wheel is properly attached to inducer motor shaft.
Verify inducer motor shaft is turning. In 460V units check the
transformer designed for the inducer motor is operational. Also
check the fuses for the inducer motor transformer (460V units only).
The burner thermal switch will automatically reset, but IGC will
continue to lockout unit.
Check any possible blockage in the access panel louver, intake
tube connected to the burner box, and the flue gas exhaust.
Check gas valve operation.
Ensure that induced-draft blower wheel is properly secured to motor
shaft.
Inspect the burner mesh inside the burner box by opening the side
window on the burner box.
Reset the unit disconnect.
If error code is not cleared by resetting unit power, replace the IGC
board.
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