Mitsubishi Electric PUMY-P100VHM Technical & Service Manual page 40

Display
Meaning and detecting method
5102
Liquid pipe temperature thermistor (TH22)
abnormality
When the thermistor detects short/open
during the 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 abnormally. In this time,
<5102> is displayed. Then, if the
thermistor recover in 3 minutes, it operates
normally.
Short: Detected 90; or more
Open: Detected -40; or less
Low pressure saturation temperature
thermistor (TH6) abnormality
1
When controller detects short/open in
thermistor during the operation, the outdoor
unit stops once and restarts operation in
3minutes. When the detected temperature
is normal at just before of restarting, the
outdoor unit restarts.
2
When controller detects short/open in
thermistor at just before of restarting, the
unit stops abnormally. In this time, <5102>
is displayed.
3
For 10 minutes after starting compressor in
heating mode, above-mentioned short/open
are not detected.
Short: 90; or more
Open: -40; or less
Causes
1) Connector (CN21) contact failure
2) Thermistor wiring disconnection or
half disconnection
3) Thermistor failure
4) Detecting circuit failure in the
indoor controller board
1) Connector (TH6) contact failure
2) Thermistor wiring disconnection or
half disconnection
3) Thermistor failure
4) Multi controller board input circuit
failure
40
Check points
1
Check whether the connector
(CN21) in the indoor controller board
is connected or not.
2
Check whether the thermistor wiring
is disconnected or not.
3
Check the resistance of thermistor;
0;····15k'
10;···9.6k'
20;···6.3k'
30;···4.3k'
40;···3.0k'
4
When there is no problem in above
mentioned 123,replace the indoor
controller board.
1
Check whether the connector (TH6)
in the multi controller board is
connected or not.
2
Check whether the thermistor wiring
is disconnected or not.
3
Check the resistance of thermistor;
0;····15k'
10;···9.6k'
20;···6.3k'
30;···4.3k'
40;···3.0k'
1 3 4 5 6 7 8 2
4
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