Troubleshooting - Carrier 48LJE004 Installation, Start-Up And Service Instructions Manual

TROUBLESHOOTING
Table 18 — LED Error Code Service Analysis
PROBLEM
CAUSE
REMEDY
Hardware failure.
(LED OFF)
Loss of power to control module (IGC).
Check 5 amp fuse on IGC, power to unit, 24 v circuit
breaker, and transformer. Units without a 24 v circuit
breaker have an internal overload in the 24 v trans¬
former If the overload trips, allow 10 minutes for auto¬
matic reset.
Limit switch fault.
(LED 2 flashes)
High temperature limit switch is open.
Check the operation of the indoor (evaporator) fan mo¬
tor. Ensure that the supply-air temperature rise is in ac¬
cordance with the range on the unit nameplate.
Flame sense fault.
(LED 3 flashes)
The IGC sensed flame that should not be present
Reset unit. If problem persists, replace control board
4 consecutive limit
switch trips.
(LED 4 flashes)
Inadequate airflow to unit.
Check operation of indoor (evaporator) fan motor and
that supply-air temperature rise agrees with range on
unit nameplate information.
Ignition lockout.
(LED 5 flashes)
Unit unsuccessfully attempted ignition for 15 minutes.
Check ignitor and flame sensor electrode spacing, gaps,
etc. Ensure that flame sense and ignition wires are prop¬
erly terminated. Verify that unit is obtaining proper
amount of gas.
Induced-draft motor
fault.
(LED 6 flashes)
IGC does not sense that induced-draft motor is
operating.
Check for proper voltage. If motor is operating, check
the speed sensor plug/IGC Terminal J2 connection.
Proper connection: PIN 1 — White, PIN 2 — Red, PIN 3
— Black.
Rollout switch fault.
(LED 7 flashes)
Rollout switch has opened.
Rollout switch will automatically reset, but IGC will con¬
tinue to lockout unit. Check gas valve operation. Ensure
that induced-draft blower wheel is properly secured to
motor shaft. Reset unit at unit disconnect.
Internal control fault.
(LED 8 flashes)
Microprocessor has sensed an error in the software or
hardware.
If error code is not cleared by resetting unit power, re¬
place the IGC.
IMPORTANT: Refer to Table 19 - Heating Service Analysis for
additional troubleshooting analysis.
LEGEND
IGC
— Integrated Gas Unit Controller
LED
— Light-Emitting Diode
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