Trouble Criterion Of Main Parts; Defrost Thermistor (Rt61); Compressor; Outdoor Fan Motor - Mitsubishi Electric MXZ-2B20NA Service Manual

11-5. TROUBLE CRITERION OF MAIN PARTS

MXZ-2B20NA MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA MXZ-5B42NA
Part name

Defrost thermistor (RT61)

Fin temperature
thermistor (RT64)
MXZ-2B/3B/4B
Ambient temperature
thermistor (RT65)
Outdoor heat exchanger
temperature thermistor
(RT68)
Discharge temperature
thermistor (RT62)

Compressor

W
RED
V
U
WHT
BLK

Outdoor fan motor

MXZ-2B/3B/4B
RED
U (W)
WHT
(V)
V
BLK
(U)
W
Outdoor fan motor
MXZ-5B
R. V. coil
Solenoide coil
MXZ-5B
Linear expansion valve
MXZ-2B
WHT
LEV
RED
ORN
YLW BRN
BLU
The other models
WHT
LEV
RED
ORN
YLW BLU
High pressure switch
(HPS)
MXZ-3B/4B/5B
OBH560G
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.
Measure the resistance between terminals using a tester.
(Winding temperature: 14°F ~ 104°F)
MXZ-2B20NA MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA
0.86 Ω ~ 1.06 Ω
Measure the resistance between lead wires using a tester.
(Part temperature: 14°F ~ 104°F)
Normal (Each phase)
MXZ-2B20NA -
MXZ-2B20NA
13.4 Ω ~ 16.4 Ω
• Refer to 11-6. .
Measure the resistance using a tester. (Part temperature: 14°F ~ 104°F)
MXZ-2B20NA MXZ-2B20NA - MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA
1
1.2 Ω ~ 1.56 Ω
Measure the resistance using a tester. (Part temperature: 14°F ~ 104°F)
Normal
MXZ-5B42NA
1.17 Ω ~ 1.43 Ω
Measure the resistance using a tester. (Part temperature: 14°F ~ 104°F)
Color of lead wire
MXZ-2B20NA -
MXZ-3B24NA
MXZ-2B20NA
MXZ-3B30NA
MXZ-4B36NA
MXZ-5B42NA
WHT - RED
WHT - RED
RED - ORN
RED - ORN
BRN
YLW -
YLW - RED
BRN - BLU
RED - BLU
HPS
Check method and criterion
Normal (Each phase)
1.29 Ω ~ 1.49 Ω
MXZ-3B24NA MXZ-3B30NA MXZ-4B36NA
1
13 Ω ~ 16 Ω
Normal
1
37.4 Ω ~ 53.9 Ω
Pressure
537 ± 22 PSIG
+ 7
696 PSIG
-
15
65
MXZ-5B42NA
0.47Ω ~ 0.57 Ω
MXZ-5B42NA
1.26 Ω ~ 1.62 Ω
Normal
Normal
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