104
Check code name
[P20] / [22]
(Current code / AI-NET)
Check code name
High-pressure protective operation
Cause of operation
1. Pd sensor error
2. Service valve closed.
3. Indoor/outdoor fan error
4. Indoor/outdoor PMV clogging
5. Indoor/outdoor heat exchanger clogging
6. SV2 circuit error
7. SV4 circuit error
8. SV5 circuit error
9. Outdoor I/F P.C. board error
10. Operation error of check valve of main
discharge pipe
11. Refrigerant overcharge
Is there no fan crack or coming-off?
Is outdoor PMV normal?
Is SV2 circuit normal?
Is SV4 circuit normal?
Are service valves fully opened?
Reset power supply, and start a test
operation corresponded to the season.
Does cooling outdoor fan
normally operate?
Does check valve of main
discharge pipe normally operate?
Refrigerant overcharge, clogging,
pipe breakage, abnormal overload condition
Are characteristics of
high-pressure sensor normal?
Open service valves fully.
Check parts.
Failure
Replace
* 1. Pressure by pressure gauge (Check joint)
2. Pressure display on 7-segment display
3. Output voltage of I/F P.C. board
If 1 and 2, 3 are different, an error of pressure sensor is considered.
If 2 and 3 are different, check I/F P.C. board.
Is there a cause to interfere operation
of heat exchanger of outdoor unit?
1. Heat exchanger clogging
2. Air short circuit
Cooling
To B
Heating
To C
B Cooling operation
Correct faulty parts.
Correct faulty parts.
Correct faulty position.
Eliminate the interfered causes.
Repair SV2 circuit.
Repair check valve.
Replace
Repair SV4 circuit.
(Connector connection, fan IPDU, fan motor, cabling)
(Connector connection wiring, coil mounting, valve clogging, etc)
(Coil error, clogging, disconnection of cable, etc.)
(Coil error, clogging, disconnection of cable, etc.)
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
FILE NO. SVM-05052
Summary of Contents for MMK-AP0072H
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