Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 1081

6
Error display:
Indoor unit
Red LED Stays OFF
Green LED Keeps flashing
Is the outdoor
unit heat exchanger
hermistor connector
OK?
NO
Repair
7
Error display:
Indoor unit
Red LED Stays OFF
Green LED Keeps flashing
Is the outdoor
air temperature thermistor
connector connection
OK?
NO
Repair
[Defective outdoor unit heat exchanger thermistor]
Outdoor unit
Red LED
Green LED
Are the outdoor
YES
unit heat exchnger thermistor
characteristics OK, is there
any broken wire?
NO
Defective outdoor unit
heat exchanger thermistor
→ Replacement
[Defective outdoor temperature thermistor]
Outdoor unit
Red LED
Green LED
Is the outdoor
YES
temperature thermistor
characteristics OK, is there
no broken wire?
NO
Defective outdoor
temperature thermistor
→ Replacement
Keeps flashing
Keeps flashing
Defective outdoor unit PCB →
YES
Replacement (Defective outdoor
unit heat exchanger thermistor
input circuit)
Outdoor unit heat exchanger
thermistor (Th
temperature characteristics
15
10
5
Keeps flashing
Keeps flashing
Defective outdoor unit PCB →
YES
Replacement (Defective outdoor
temperature thermistor input
cicuit)
Temperature-resistance
characteristics of outdoor
temperature thermistor (Th
400
300
T < 0°C
200
100
0
-50
Temperature [T] (°C)
FDC-HKXR
R) Resistance
O-
5k Ω at 25°C
0 10 20 30 40 50
Temperature (°C)
A)
O-
40
30
20
T > 0°C
10
0
0 50
1079