Service manual

Si18-201 Troubleshooting - Outdoor Unit Related
Service Diagnosis 287
3.3.24 Electronic Thermal
Outdoor Unit
Indication
L8
Method of
Malfunction
Detection
Electronic thermal is detected using output amperage and operating status.
Malfunction
Decision
Conditions
When the compressor output current of 40A or higher continued for 260 seconds
When the compressor output current of 50A or higher continued for 5 seconds
"
When an electronic thermal error is generated 4 times, the system shuts down.
(The 4-time counter resets itself when no outdoor unit abnormality occurs for 60-minute
cumulative time after the error generation.)
Supposed
Causes
"
Incorrect connectors connection
"
Faulty thermistor
"
Faulty power transistor
"
Disconnection·Faulty connection of internal wiring
"
Faulty reactor
"
Faulty compressor
"
Faulty PC board
Troubleshooting
Check No.5
Refer to P.302
Check No.6
Refer to P.303
Check No.7
Refer to P.304
Check No.1
Refer to P.300
Check No.2
Refer to P.300
Check No. 5
Main circuit wiring
connection check
NO
Replace control PC board.
Apply required remedy
subject to the case.
Apply required remedy
subject to the case.
Apply required remedy
subject to the case.
When halting,
does the current stated
above?
(MF043)
YES
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Check output current
(Measure motor current of
U,V,W with use of clamp meter.)
Check No. 6
Power transistor check
Check No. 7
Power transistor output check
OK
Check No. 1
Installation conditions check
OK
Check No. 2
Discharge pressure check