Temperature Sensor - Mitsubishi Electric PURY-M200YNW-A1 Service Handbook

[8-9 Troubleshooting Problems with Major Components on HBC ]
8-9-2

Temperature Sensor

1) Connectors on the circuit board are connected to the sensors as follows. Unplug the corresponding connectors before check-
ing each sensor.
Sensor
TH11,TH13
TH12,TH14
TH15,TH16
TH31a,TH31b,TH31c
TH31d,TH31e,TH31f
TH31g,TH31h
TH31i,TH31j,TH31k
TH31l,TH31m,TH31n
TH31o,TH31p
TH32,TH35
TH33,TH34
VB board 1 is the one on the right when facing the control box.
VB board 2 is the one on the left when facing the control box.
2)
Pull out the sensor connector from the VB board, Do not pull the sensor by holding the lead wire.
Measure the resistance with such as a tester.
Compare the measured value with that of shown in the figure below. When the result is
36
- chapter 8
Troubleshooting instructions for thermistor
START
Pull out the thermistor connector in
trouble from the board.
Measure the temperature of the thermistor
in trouble. (actual measurement value)
Check the thermistor resistor.
Compare the temperature corresponding to the
resistance measured by the thermistor and the
temperature measured by a commercially
available thermometer, and check whether
there is no difference between them.
Temperature difference
NO
Insert the connector of the thermistor
in trouble into the board, check the sensor
inlet temperature on the LED monitor,
and check the temperature difference.
Temperature difference
NO
Normal
Circuit board
Control board
Control board
Control board
VB board 1
VB board 1
VB board 1
VB board 2
VB board 2
VB board 2
Control board
Control board
Note 1
Note 2
Note 2
YES
Replace the thermistor
Note 3
YES
Check for contact failure.
Replace the control board.
Connector
CN401
CN402
CN403
CNTH1
CNTH2
CNTH3
CNTH1
CNTH2
CNTH3
CN404
CN405
10%, it is normal.
BS_08_L