Mitsubishi PUMY-P100YHM Technical & Service Manual page 43

Display
Abnormal point and detecting method
5103
Gas pipe temperature thermistor (TH23)
When the thermistor detects short/open
after 3 minutes-continuous thermo ON
during cooling or dry operation, the
operation stops and the operation
changes to protect mode of restarting in 3
minutes. If the thermistor does not
recover in 3 minutes, the operation stops
due to detecting abnormality. In this time,
<5103> is displayed. Then, if the
thermistor recover in 3 minutes, it
operates normally.
Short: Detected 90
Open: Detected -40
5105
Pipe temperature / judging defrost
thermistor (TH3)
When controller detects short/open in
thermistor during the operation, the outdoor
unit stops once and restarts operation in 3
minutes. When the detected temperature is
normal at just before of restarting, the
outdoor unit restarts.
When controller detects short/open in
thermistor at just before of restarting, the
unit stops due to detecting abnormality. In
this time, <5105> is displayed.
For 10 minutes after starting compressor,
for defrosting or for 3 minutes after recover
of defrosting, above-mentioned short/open
are not detected.
Short: 88 or more (0.4k )
Open: -39 or less (115k )
1) Connector (CN29) contact failure
2) Thermistor wiring disconnection or
half disconnection
3) Thermistor failure
or more
or less
4) Detecting circuit failure in the indoor
1) Connector (TH3) contact failure
2) Thermistor wiring disconnection or
3) Thermistor failure
4) Multi controller board input circuit
Causes
controller board
half disconnection
failure
43
Check points
Check whether the connector (CN29)
in the indoor controller board is
connected or not.
Check whether the thermistor wiring
is disconnected or not.
Check the resistance of thermistor;
0 ····15k
10 ···9.6k
20 ···6.3k
30 ···4.3k
40 ···3.0k
When there is no problem in above
mentioned , replace the indoor
controller board.
Check whether the connector (TH3)
in the multi controller board is
connected or not.
Check whether the thermistor wiring
is disconnected or not.
Check the resistance of thermistor;
When the resistance is not below
value, replace the thermistor.
0 ····15k
10 ···9.6k
20 ···6.3k
30 ···4.3k
40 ···3.0k
1 3 4 5 6 7 8 2
on
Set the SW1 to
When the temperature in multi
controller board is not an actual
temperature, replace the multi
controller board.
-42.5: Open
91.9: Short