Troubleshooting - Mitsubishi Electric PKFY-P20VAM-A Technical & Service Manual

7

TROUBLESHOOTING

7-1. How to check PKFY-P20VAM-A, PKFY-P25VAM-A
Part Name
Room temperature Disconnect the connector, then measure the resistance using a tester.
thermistor(TH21)
(Surrounding temperature 10°C~30°C)
Liquid pipe temperature
thermistor(TH22)
Gas pipe temperature
thermistor(TH23)
Vane motor 1Measure the resistance between the terminals using a tester.(Surrounding temperature 25:.)
3 Blue
M
Yellow
5
Red
1
Orange Pink
Connect pin No.
4 2
Fan motor
1Measure the resistance between the terminals using a tester.(Surrounding temperature 20:.)
FAN
1
White
Red
4
Black
6
2Without disassembling the parts, measure the electrical pressure of the gray wire(Signal line) and
Brown Gray Yellow
3 2 1
CN34
Linear expansion Disconnect the connector then measure the resistance valve using a tester.
(Coil temperature 20°C)
valve
CN60
White
1
Yellow
2
Orange
3
LEV White-Red
Blue
4
Red
5
Brown
6
Normal
4.3k ~9.6k Open or short
' '
Normal
1-2 1-3
Red-Pink Red-Blue
400'
White-Black
Red-Black
brown wire (GND) while the power is on.
!At first, check if the electrical pressure is 12V between the
brown wire(GND) and yellow wire(VCC).
Normal
@Slowly start running the fan. It is normal if while the fan rotate once,
the electrical pressure change from 0V to12V then go back to 0V.
If the electrical pressure stay at around 0V or 10V, it means the fan
Abnormal
motor has the defects.
Normal
(1)-(5) (2)-(6)
Yellow-Brown
150'
Check points
Abnormal
(Refer to the next page for a detail.)
1-4 1-5
Red-Orange Red-Yellow
± 7%
Normal
195'
200'
(3)-(5) (4)-(6)
Orange-Red Blue-Brown
±10%
12
Abnormal
Open or short
Abnormal
Open or short
Abnormal
Open or short