3-84
Check code
Operation cause
[bb]
Discharge temperature TD2 alarm
1. Outdoor unit service valve closed
2. Blockage of check valve to interrupt the liquid line.
3. Outdoor PMV A error or cooling bypass PMV B error
4. TD sensor error
5. Insufficient refrigerant, blockage in pipe
Check code
Operation cause
[bd]
Mg-SW protective operation
1. Mg-SW contact deposit protective operation
2. TD sensor error
3. Pd sensor/Ps sensor error
4. Insufficient refrigerant, blockage in pipe
YES
YES
YES
YES
YES
NO
NO
NO
NO
Open service valve fully.
Cooling bypass PMV B error
Replace TD2 sensor.
Set normal wiring.
Are resistance characteristics
of TD2 sensor normal?
Are gas pipe,liquid pipe,
and service valve of the
outdoor unit fully open?
Is cooling bypass PMV B normal?
Is wiring correct?
Insufficient refrigerant,
blockage, pipe breakage
NO
Repair outdoor PMV A.
1. Connector connection
2. Wiring
3. Coil
4. Valve unit
5. Outdoor P.C. board
Is outdoor PMV A normal?
NO
YES
YES
Replace the check valve
In there blockage in
the check valve to interrupt
the liquid line?
*
In cooling
only model
( )
( )
Check miswiring of the outdoor unit
according to miswiring check function.
Check there is no blockage or pipe
breakage, and then addrefrigerant according
to judgment of refrigerant amount.
YES
YES
YES
NO
NO
NO
Turn off power supply,
and replace Mg-SW.
Sensor error
Sensor error
Is contact of Mg-SW defunct?
Is resistance value characteristics
of TD sensor normal?
Are output voltage characteristics
of Pd sensor/Ps sensor normal?
Insufficient refrigerant, blockage
