Mitsubishi Heavy Industries SRK100VNXWZRF Service Manual page 137

Error code
Remote control: E57
1. Applicable model
Model FDC100VNP-W
2. Error detection method
• Judge insufficient refrigerant
amount by detecting the
temperature differnce between
indoor heat exchanger (Th2)
and room air (Th1).
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 sensor
• Defective indoor room air
temperature sensor
• Defective indoor unit control
PCB
• Insufficient refrigerant
amount
Note: When the compressor speed is faster than 40 rps or 60 rps
satisfying the under condition for 5 minutes, that it is in the state of gas leakage, and stops the compressor.
Cooling: Room air temperature (Th1) – Indoor heat exchanger temperature (Th2) < 4 deg C
Heating: Indoor heat exchanger temperature (Th2) – Room air temperature (Th1) < 4 deg C
※1 : In case of heating at low air temperature.
※2
: Cooling is 5 minutes, heating is 9 minutes.
RUN light TIMER light
Indoor
7-time
display
ON
flash
5. Troubleshooting
Diagnosis
Is the
service valve fully
opened?
YES
Are the
connections of indoor
heat exchanger and/or room air
temperature sensor
connectors OK?
YES
Are the
characteristics of indoor heat
exchanger and/or room air
temperature sensor
OK?
YES
Is the low
pressure during operation
normal?
Indoor heat exchanger, room air temperature sensor
Temperature-resistance characteristics
(Broken wire)
15
10
5
(Short-circuit)
0
※1
after several minutes
136
-
Insufficient refrigerant amount
Content
or detection of service valve closure
(Model FDC100VNP-W only)
NO
NO
For the characteristics of indoor heat
exchanger,room air temperature sensor,
see the following graph.
NO
NO
YES
5k at 25°C
10 20 30 40 50
Temperature (°C)
※2
from compressor start, the low refrigerant protection control judges, by
-
'22 • PAC-SM-422
Countermeasure
Open fully.
Correct indoor heat
exchanger, room air
temperature sensor
connector connections.
Defective indoor heat
exchanger, room air
temperature sensor
➞Replace.
Charge refrigerant.
Defective indoor unit
control PCB➞Replace.
(Defective indoor heat
exchanger, room air
temperature sensor input
circuits)