Abnormal Refrigerant Circuit - Mitsubishi Electric SUZ-KA24NAHZ Service Manual

Check Code Abnormal point and detection method

Abnormal refrigerant circuit

During Cooling, Dry, or Auto Cooling
operation, the following conditions are
regarded as failures when detected for 1
second.
a) The compressor continues to run for 30
or more seconds.
PL
b) The liquid pipe temperature or the
condenser/evaporator temperature is
167˚F [75˚C] or more.
These detected errors will not be
cancelled until the power source is
reset.
OCH754A
Cause
1 Abnormal operation of 4-way
valve
2 Disconnection of or leakage in
refrigerant pipes
3 Air into refrigerant piping
4 Abnormal operation (no rotation)
of indoor fan
· Defective fan motor.
· Defective indoor control
board.
5 Defective refrigerant circuit
(clogging)
35
Judgment and action
1 When this error occurs, be sure to
replace the 4-way valve.
2 Check refrigerant pipes for disconnection or
leakage.
3 After the recovery of refrigerant, vacuum
dry the whole refrigerant circuit.
4 Refer to section "10-5. HOW TO CHECK
THE PARTS".
5 Check refrigerant circuit for operation.
To avoid entry of moisture or air into
refrigerant circuit which could cause
abnormal high pressure, purge air in
refrigerant circuit or replace refrigerant.