Mitsubishi Electric PUHZ-W50VHA Service Manual page 30

Abnormal point and detection method
Error Code
Inlet water temperature
Abnormal if the following conditions are
detected for continuously 10 seconds.
1. Cooling mode
During compressor operation
TH32 < 3:
2. Heating mode (exclude defrosting)
During compressor operation
PE
TH32 < -10:
3. Defrosting mode
During compressor operation
TH32 < 0:
Thermistor
TH32: Inlet water temperature
8-4. HOW TO CHECK THE PARTS
PUHZ-W50VHA(-BS) PUHZ-W85VHA(-BS) PUHZ-HW112YHA(-BS)
PUHZ-HW140V/YHA(-BS)
Parts name
TH3: Liquid pipe
Disconnect the connector then measure the resistance with a tester.
temperature
(At the ambient temperature of 10 ~30 )
TH4: Discharge
temperature
TH6: Plate Hex liquid
TH4/TH33(W50)
pipe temperature
TH7: Ambient
temperature
TH8: Heatsink
temperature
TH33(HW112,140)
TH32: Inlet water
temperature
TH33:
Comp. surface
thermistor (W50),
Suction pipe temperature
(HW112,140)
Fan motor (MF1) Refer to the next page.
Solenoid valve coil Measure the resistance between the terminals with a tester.
(At the ambient temperature of 20 )
<Four-way valve>
(21S4)
Measure the resistance between the terminals with a tester.
Compressor
(Winding temperature 20 )
U
(MC)
V
W
Linear expansion valve
Disconnect the connector then measure the resistance with a tester.
(LEV-A) (LEV-B)(LEV-C)
(Winding temperature 20°C)
Gray
M
1
2
Orange
3
Red
4
Yellow
5
Black
6
Solenoid valve coil
Measure the resistance between the terminals with a tester.
(At the ambient temperature of 20 )
<Bypass valve>
(SV) W50,85
1 Reduced water flow
2 Low temperature
3 Defective water pump
4 Leakage or shortage of
Normal
160k ~410k
TH3
TH6
4.3k ~9.6k
TH7
TH32 4.4k ~9.8k
TH8 39k ~105k
Normal
W50,85 HW112,140
2350±170 1435±150
W50 W85
0.865 ~0.895
0.640
Gray - Black Gray - Red
Normal
1450±150
Case
· Clogged filter
· Leak of water
· Low-load
· Low temperature inlet water
refrigerant
Check points
Abnormal
Open or short
Abnormal
Open or short
Normal
HW140V HW112,140Y
0.188
Normal
Gray - Yellow
46±3Ω
Abnormal
Open or short
30
Judgment and action
12 Check water piping.
3 Check water pump.
4 Check intake superheat.
Check leakage of refrigerant.
Abnormal
Open or short
0.302
Gray - Orange
Open or short
Abnormal