Troubleshooting; Check Methods - Mitsubishi Electric PEFY-P25VMA-E Technical & Service Manual

[ VII Troubleshooting ]
VII Troubleshooting

[1] Troubleshooting

1. Check methods

1. Component and check points
(1) Thermistor
Room temperature thermistor (TH21)
Liquid pipe thermistor (TH22)
Gas pipe thermistor (TH23)
Disconnect the connector and measure the resistance between terminals with a tester.
(Ambient temperature 10°C - 30°C)
Normal
4.3kΩ - 9.6kΩ
(Refer to the thermistor characteristic graph below.)
1) Thermistor characteristic graph
Low-temperature thermistor
Room temperature thermistor (TH21)
Liquid pipe thermistor (TH22)
Gas pipe thermistor (TH23)
Drain sensor (DS)
Thermistor R = 15 kΩ 3%
0
Multiplier of B = 3480 kΩ 2%
Rt = 15 exp { 3480(
0°C 15kΩ
10°C 9.6kΩ
20°C 6.3kΩ
25°C 5.2kΩ
30°C 4.3kΩ
40°C 3.0kΩ
(A) Temperature
(B) Resistance
(2) Fan motor (CNMF)
Refer to the page on "DC fan motor (fan motor/indoor control board)."
(3) Linear expansion valve
Disconnect the connector, and measure the resistance between terminals with a tester.
Refer to the next page for details.
CN60
(F)
1
(E)
2
(D)
3
M
(C)
4
(B)
5
LEV
(A)
6
(A) Brown
(B) Red
(C) Blue
HWE08120
Abnormal
Open or short
1 1
) }
273+t 273
(°C)
(kΩ)
1-5 2-6
White-Red Yellow-Brown
200 kΩ 10%
(D) Orange
(E) Yellow
(F) White
50
40
30
20
10
0
-20 -10 0 10
(A)
Normal
3-5
Orange-Red Blue-Brown
- 13 -
20 30 40 50
Abnormal
4-6 Open or short
GB