Service Manual

85
11-5. TROUBLE CRITERION OF MAIN PARTS
MXZ-2C20NA2 MXZ-3C24NA MXZ-3C30NA MXZ-4C36NA
MXZ-5C42NA MXZ-2C20NAHZ MXZ-3C24NAHZ MXZ-3C30NAHZ
MXZ-3C24NA2 MXZ-3C30NA2 MXZ-4C36NA2 MXZ-5C42NA2
MXZ-2C20NAHZ2 MXZ-3C24NAHZ2 MXZ-3C30NAHZ2
W
U
V
WHT
RED
BLK
LEV
WHT
RED
YLW
ORN
BLU
Linear expansion valve
37.4 - 53.9
NormalColor of lead wire
WHT - RED
RED - ORN
YLW - RED
RED - BLU
High pressure switch
(HPS)
Pressure
Normal
HPS
537 ± 22 PSIG
696 PSIG
Open
Close
+7
- 15
Discharge temperature
thermistor (RT62)
Measure the resistance using a tester. (Part temperature: 14°F - 104°F)
Measure the resistance using a tester. (Part temperature: 14°F - 104°F)
Part name Check method and criterion
Measure the resistance between terminals using a tester.
(Winding temperature: 14°F - 104°F)
Compressor
Outdoor fan motor
R.V. coil
Defrost thermistor (RT61)
Fin temperature
thermistor (RT64)
Ambient temperature
thermistor (RT65)
Outdoor heat exchanger
temperature thermistor (RT68)
Measure the resistance with a tester.
Refer to 11-7. “Test point diagram and voltage”, 1. ”Outdoor control P.C.board”,
2. ”Outdoor power P.C. board”, for the chart of thermistor.
Measure the resistance with a tester.
Before measurement, hold the thermistor with your hands to warm it up.
Refer to 11-7. “Test point diagram and voltage”,1. ”Outdoor control P.C. board” for the chart of thermistor.

MXZ-3C24NA MXZ-3C30NA MXZ-4C36NA
MXZ-3C24NA2 MXZ-3C30NA2 MXZ-4C36NA2
MXZ-2C20NA2
MXZ-2C20NA2
MXZ-3C24NA MXZ-3C30NA MXZ-4C36NA
MXZ-3C24NA2 MXZ-3C30NA2 MXZ-4C36NA2
Normal (Each phase)
NN
NN
NN
Normal (Each phase)
Measure the resistance between terminals using a tester.
(Winding temperature: 14°F - 104°F)

MXZ-5C42NA MXZ-2C20NAHZ MXZ-3C24NAHZ MXZ-3C30NAHZ
MXZ-5C42NA2 MXZ-2C20NAHZ2 MXZ-3C24NAHZ2 MXZ-3C30NAHZ2
MXZ-5C42NA MXZ-2C20NAHZ MXZ-3C24NAHZ MXZ-3C30NAHZ
MXZ-5C42NA2 MXZ-2C20NAHZ2 MXZ-3C24NAHZ2 MXZ-3C30NAHZ2
Normal (Each phase)
NN
Normal (Each phase)
5HIHUWR
Normal
Measure the resistance using a tester. (Part temperature: 14°F - 104°F)
2-way valve solenoid coil
MXZ-5C42NA
MXZ-2C20NAHZ
MXZ-3C24NAHZ
MXZ-3C30NAHZ
MXZ-5C42NA2
MXZ-2C20NAHZ2
MXZ-3C24NAHZ2
MXZ-3C30NAHZ2
Measure the resistance using a tester. (Part temperature: 14°F - 104°F)
NN
MXZ-5C42NA
MXZ-2C20NAHZ
MXZ-3C24NAHZ
MXZ-3C30NAHZ
MXZ-5C42NA2
MXZ-2C20NAHZ2
MXZ-3C24NAHZ2
MXZ-3C30NAHZ2
Normal
Measure the resistance using a tester. (Part temperature: 14°F - 104°F)
Defrost heater
MXZ-2C20NAHZ
MXZ-3C24NAHZ
MXZ-3C30NAHZ
MXZ-2C20NAHZ2
MXZ-3C24NAHZ2
MXZ-3C30NAHZ2
0.35N - 0.50N
OBH702F