-
278
-
'17 • SCM-T-225
Error code
Remote control:
LED
Green
Red
Content
Indoor
Stays OFF
Keeps flashing
E57
Insufficient refrigerant amount
or detection of service valve closure
Outdoor
–
2
-
time flash
1. Applicable model
5. Troubleshooting
All models
Diagnosis
Countermeasure
NO
YES
NO
YES
Is the
service valve fully
opened?
Are the
connections of indoor
heat exchanger and/or return air
temperature thermistor
connectors OK?
NO
YES
NO
YES
Are the
characteristics of indoor heat
exchanger and/or return air
temperature thermistor
OK?
Is the low
pressure during operation
normal?
Indoor heat exchanger, return air temperature thermistor
Temperature-resistance characteristics
15
10
5
0
10
30
40
20
50
Temperature thermistor resistance (k
Ω
)
Temperature (°C)
5k
Ω
at 25°C
(Broken wire)
(Short circuit)
Open fully.
Correct indoor heat
exchanger, return air
temperature thermistor
connector connections.
Defective indoor heat
exchanger, return air
temperature thermistor
➞
Replace.
Charge refrigerant.
Defective indoor control
PCB
➞
Replace. (Defective
indoor heat exchanger,
return air temperature
thermistor input circuits)
2. Error detection method
• Judge insufficient refrigerant
amount by detecting the
temperature differnce between
indoor heat exchanger (Thi-R)
and indoor return air (Thi-A).
3. Condition of error displayed
When the insufficient refrigerant
amount is detected 3 times
within 60 minutes.
4. Presumable cause
• Defective indoor heat
exchanger temperature
thermistor
• Defective indoor return air
temperature thermistor
• Defective indoor control PCB
• Insufficient refregerant
amount
Note: