SiAF341904E
Troubleshooting by Error Code
Part 6 Service Diagnosis
243
5.38 Inverter Radiation Fin Temperature Rise Abnormality
Applicable
Models
All outdoor unit models
Error Code
L4
Method of Error
Detection
Detect temperature of power module of the inverter PCB and fan PCB.
Error Decision
Conditions
Thermistor located inside the power module of the inverter PCB for compressor and fan motor.
Cooling tube plate poor heat-exchange.
Supposed
Causes
Radiation fin temperature rise of fan PCB.
Cooling tube plate not fixed with screws.
U0
error.
Defective inverter PCB.
High outdoor air temperature.
Troubleshooting
Subcode L4-01, 02, 03, 09, 10, 11
Continue operation.
Field factor. Power module temperature
may have risen due to high outdoor air
temperature.
Turn ON the
power supply, and then
press the ON button
continuously. Does
the error
recur?
Replace the inverter PCB.
RXQ6-14A: A3P
RXQ16-20A: A3P, A6P
YES
Rectify troubles.
Normal?
NO
NO
Check for the cooling
conditions of cooling tube
used to cool the inverter.
(1) Is the cooling tube plate
fixed with screws?
(2) Error code
U0
is displayed
on the Error History
screen.
YES
For the models equipped with
2 compressors, check the
compressor M1C or M2C
applicable to the error code
L4
while in monitor mode of
the outdoor unit.
Check in Monitor Mode
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
