MXS Service Manual

Troubleshooting for Outdoor Unit SiUS121736EA
205 Service Diagnosis
7.18 Electrical Box Temperature Rise
Error Code L3
Outdoor Unit LED
Display
A j 1 i 2 i 3 h 4 i 5 h
Method of Error
Detection
An electrical box temperature rise is detected by checking the radiation fin thermistor with the
compressor off.
Error Decision
Conditions
 With the compressor off, the radiation fin temperature is above A.
 The error is cleared when the temperature drops below
B.
 To cool the electrical components, the outdoor fan starts when the radiation fin temperature
rises above
C and stops when it drops below B.
Supposed
Causes
 Defective outdoor fan motor
 Short circuit
 Defective radiation fin thermistor
 Disconnection of connector
 Defective outdoor unit PCB
Troubleshooting
Check No.17
Refer to P.216
Check No.19
Refer to P.217
ABC
100°C (212°F) 70°C (158°F) 85°C (185°F)
Caution
WARNING
To cool the electrical components,
the outdoor fan starts when the
radiation fin temperature rises
above C. The outdoor fan stops
when the radiation fin temperature
drops below B.
(R22272)
YES
NO
YES
NG
NO
OK
NO
YES
Turn off the power. Then, turn on
the power to restart the system.
Check the radiation fin
temperature.
Radiation fin dirty?
Check No. 19
Check the outdoor fan.
Error again or outdoor
fan activated?
Replace the outdoor unit
PCB (main PCB).
Clean up the radiation fin.
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Replace the outdoor fan
motor.
Correct the connectors
and fan motor lead wire.
Replace the outdoor unit
PCB (main PCB).
Above A?
Check the installation
condition.
Go to Check No. 17.