Mitsubishi Electric MUFZ-KW25VG-E1 Service Manual page 38

12-4. TROUBLESHOOTING CRITERION OF MAIN PARTS
MUFZ-KW25VGHZ MUFZ-KW35VGHZ MUFZ-KW50VGHZ MUFZ-KW60VGHZ
Part name
Defrost thermistor (RT61) Measure the resistance with a tester.
Refer to 12-6. "Test point diagram and voltage", 1. "Inverter P.C.
Fin temperature
board", for the chart of thermistor.
thermistor (RT64)
Ambient temperature
thermistor (RT65)
Outdoor heat exchanger
temperature thermistor
(RT68)
Measure the resistance with a tester. Before measurement, hold the
thermistor with your hands to warm it up.
Discharge temperature
thermistor (RT62)
Refer to 12-6. "Test point diagram and voltage", 1. "Inverter P.C.
board", for the chart of thermistor.
Measure the resistance between terminals using a tester.
(Temperature: -10 to 40°C)
Compressor
Measure the resistance between lead wires using a tester.
(Temperature: -10 ~ 40°C)
Outdoor fan motor
Measure the resistance using a tester. (Temperature: -10 to 40°C)
R.V. coil (21S4)
Measure the resistance using a tester. (Temperature: -10 to 40°C)
Expansion valve coil
(LEV)
Measure the resistance using a tester. (Temperature: -10 to 40°C)
Defrost heater
OBH895
Check method and criterion
Normal (Ω)
MUFZ-KW25VGHZ
MUFZ-KW35VGHZ
U-V
U-W 0.82 - 1.11
V-W
Color of lead wire
MUFZ-KW25VGHZ
MUFZ-KW35VGHZ
RED – BLK
BLK – WHT 32 - 43
WHT – RED
Normal (kΩ)
MUFZ-KW25VGHZ MUFZ-KW50VGHZ
MUFZ-KW35VGHZ MUFZ-KW60VGHZ
1.41 - 2.00
Normal (Ω)
Color of lead wire
RED – ORN
RED – WHT
37 - 54
RED – BLU
RED – YLW
Normal (Ω)
MUFZ-KW25VGHZ MUFZ-KW50VGHZ
MUFZ-KW35VGHZ MUFZ-KW60VGHZ
802 - 990
MUFZ-KW50VGHZ
MUFZ-KW60VGHZ
0.87 - 1.18
Normal (Ω)
MUFZ-KW50VGHZ
MUFZ-KW60VGHZ
25 - 34
1.17 - 1.66
376 - 461
38
Figure
WHT RED BLK
W
V
U
WHT RED BLK
W
V
U
WHT
LEV
ORN
RED
(+12V)