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Operation of diagnostic function
Check code
Status of
air conditioner
Condition
Cause of operation
Judgment and measures
Indoor unit
P26
Short-circuit trouble of compressor
driving element
Stop
Displayed when
trouble is detected
1. When performing operation while taking-off compressor
wire, P26 trouble occurs. Check control P.C. board
(MCC-1698).
2. When performing operation while taking-off compressor
wire, an trouble does not occur. (Compressor layer short)
H04
Case thermostat operation
∗
Abnormal overheat of compressor
Stop
Displayed when
trouble is detected
1. Check case thermostat and connector.
2. Check gas leak, recharge
3. Check full open of service valve.
4. Check PMV (Pulse Motor Valve).
5. Check broken pipe.
P04
High pressure SW system trouble
Stop
Displayed when
trouble is detected
1. Check service valves are fully opened.
(Gas side, Liquid side)
2. Check of outdoor fan operation.
3. Check motor trouble of outdoor fan.
4. Check clogging of outdoor PMV. (PMV1, 2)
5. Check clogging of heat exchanger in indoor/outdoor units.
6. Short-circuit status of suction/discharge air in outdoor unit.
7. Check outdoor P.C. board trouble.
8. Check fan system trouble (Cause of air volume drop)
at indoor side.
9. Check PMV opening status in indoor unit.
High pressure SW system trouble
Stop
Displayed when
trouble is detected
1. Check service valves are fully opened.
(Gas side, Liquid side)
2. Check of outdoor fan operation.
3. Check motor trouble of outdoor fan.
4. Check clogging of outdoor PMV. (PMV1, 2)
5. Check clogging of heat exchanger in indoor/outdoor units.
6. Short-circuit status of suction/discharge air in outdoor unit.
7. Check outdoor P.C. board trouble.
8. Check fan system trouble (Cause of air volume drop)
at indoor side.
9. Check PMV opening status in indoor unit.
P03
Discharge temp. trouble
∗
Discharge temp. (TD) over
specified value was detected.
Stop
Displayed when
trouble is detected
1. Check refrigerating cycle (Gas leak)
2. Trouble of electronic expansion valve
3. Check discharge temp. sensor (TD).
P05
Power supply voltage trouble
Stop
Displayed when
trouble is detected
1. Check power supply voltage. AC342 to 457V
P29
Position detection circuit trouble
Stop
Displayed when
trouble is detected
1. Check control P.C. board (MCC-1698).
P20
High pressure protective operation
∗
During cooling operation, outdoor
temp. sensor (TL) detected
temperature over specified temp.
∗
During heating operation, indoor
temp. sensor (TC, TCJ) detected
temperature over specified temp.
Stop
Displayed when
trouble is detected
1. Check outdoor heat exchanger sensor (TL).
2. Check indoor heat exchanger sensor (TC, TCJ).
3. Check full open of service valve.
4. Check indoor/outdoor fan.
5. Check PMV (Pulse Motor Valve).
6. Check clogging and short circuit of indoor/outdoor heat
exchanger.
7. Overcharge of refrigerant. Recharge
P22
Outdoor fan system trouble
Stop
Displayed when
trouble is detected
1. Check lock of fan motor.
2. Check power supply voltage between L2 and N.
AC198 to 264V
3. Check outdoor P.C. board.