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65
11-5. TROUBLE CRITERION OF MAIN PARTS
MXZ-2B20NA MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA MXZ-5B42NA
Discharge temperature
thermistor (RT62)
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
Measure the resistance between lead wires using a tester.
(Part temperature: 14°F ~ 104°F)
Outdoor fan motor
MXZ-2B/3B/4B
Outdoor fan motor
MXZ-5B
R.
Normal
Measure the resistance using a tester. (Part temperature: 14°F ~ 104°F)
Solenoide coil
MXZ-5B
V. coil
Measure the resistance using a tester. (Part temperature: 14°F ~ 104°F)
13.4
Ω
~ 16.4
Ω
Normal (Each phase)
13
Ω
~ 16
Ω
MXZ-2B20NA - MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA
Defrost thermistor (RT61)
Fin temperature
thermistor (RT64)
MXZ-2B/3B/4B
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. “Electronic control P.C. board”,
2.”Outdoor control P.C.board”, 4. “Power board”, or 5.”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. “Electronic control P.C.
board”, or 2.”Outdoor control P.C. board”, for the chart of thermistor.
MXZ-2B
0.86
Ω
~ 1.06
Ω
1.29
Ω
~ 1.49
Ω
0.47
Ω
~ 0.57
Ω
MXZ-2B20NA
MXZ-5B42NA
MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA
Normal (Each phase)
MXZ-2B20NA
1.2
Ω
~ 1.56
Ω
Normal
1.26
Ω
~ 1.62
Ω
MXZ-5B42NA
MXZ-2B20NA MXZ-2B20NA - MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA
MXZ-2B20NA -
MXZ-3B24NA
MXZ-3B30NA
MXZ-4B36NA
MXZ-5B42NA
• Refer to 11-6. .
1.17
Ω
~ 1.43
Ω
MXZ-5B42NA
1
1
Linear expansion valve
LEV
WHT
RED
YLW BRN
ORN
BLU
The other models
WHT - RED
RED - ORN
37.4
Ω
~ 53.9
Ω
Normal
YLW -
- BLU
Color of lead wire
MXZ-2B20NA
WHT - RED
RED - ORN
YLW - RED
RED - BLU
BRN
BRN
High pressure switch
(HPS)
MXZ-3B/4B/5B
Pressure
Normal
HPS
537 ± 22 PSIG
696 PSIG
Open
Close
+ 7
-
15
1
W
U
V
WHT
RED
BLK
U
RED
WHT
BLK
V
W
(W)
(V)
(U)
LEV
WHT
RED
YLW
ORN
BLU
OBH560G