Table 18 — led error code service analysis, Troubleshooting – Carrier 48LJD User Manual
Page 26
Attention! The text in this document has been recognized automatically. To view the original document, you can use the "Original mode".
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 internai overload in the 24 v trans
former if the overload trips, aliow 10 minutes for auto
matic reset.
Limit switch fauit.
(LED 2 fiashes)
High temperature iimit switch is open.
Check the operation of the indoor (evaporator) fan mo
tor. Ensure that the suppiy-air temperature rise is in ac
cordance with the range on the unit namepiate.
Fiame sense fauit.
(LED 3 fiashes)
The IGC sensed flame that should not be present
Reset unit. If problem persists, repiace controi board
4 consecutive iimit
switch trips.
(LED 4 fiashes)
Inadequate airflow to unit.
Check operation of indoor (evaporator) fan motor and
that suppiy-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
26