Heating - Mitsubishi MXZ-4C36NAHZ Technical & Service Manual

Check code
1102
(U2)
Abnormal points and detection methods
(1) Abnormal if TH4 falls into following temperature conditions;
●exceeds 230°F [110 ] continuously for 5 minutes
●exceeds 257°F [125 ]
(2) Abnormal if a pressure detected by the high pressure sensor and
converted to saturation temperature exceeds 104°F [40 ] during
defrosting, and TH4 exceeds 230°F [110 ].
TH4: Thermistor <Compressor>
LEV: Electronic expansion valve
●Diagnosis of defectives
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
Is 5101 displayed when restarted?
Is the outdoor stop valve (liquid/
gas) fully open?
Is there a refrigerant leak?
Check the connection for thermistor wiring
and indoor controller board connector.
Is there any abnormality on
connectors/wires such as a disconnection,
half-disconnection or breakage?
Continue to the next page
OCH573C
Compressor temperature trouble
Diagnosis
(5101)
(1102)
No
Yes
ed
(no leak)
No
No
Causes and check points
Malfunction of stop valve
Over-heated compressor operation caused by
shortage of refrigerant
Defective thermistor
Defective outdoor controller board
LEV performance failure
Defective indoor controller board
Clogged refrigerant system caused by foreign
object
Refrigerant shortage while in heating operation
(Refrigerant liquid accumulation in compressor while
indoor unit is OFF/thermo-OFF.)
Yes Refer to the diagnosis of check code 5101.
Open the stop valve (liquid/ gas) fully.
No
Repair the refrigerant leakage.
Yes
Connect the connector properly
Yes
(Repair or replace it in case of a breakage).
59
Chart 1 of 2
Remedy