L10 Alarm; P02 Compressor Thermal Protector Is Activated.(Trip Only And No Alarm) - Panasonic U-8ME1E81 Service Manual

4. 2WAY Alarm Codes

L10 Alarm

Alarm code L10
Alarm meaning Outdoor unit capacity not set
Alarm conditions The outdoor unit capacity has not been set, or the setting is not allowed by the system.
Probable cause This alarm occurs because the capacity has not been set.
Check Connect the outdoor unit maintenance remote controller. On the outdoor unit EEPROM detailed
setting mode screen, check the value for the outdoor unit capacity (item code 81).
Check that it is not set to "0" or to a capacity that is not allowed.
Correction If item code 81 is incorrect, use the outdoor unit maintenance remote controller and set it
correctly.
* After changing the setting, be sure to reset both the indoor and outdoor power.
Example —
Notes The outdoor unit maintenance remote controller is required in order to set the capacity in the
outdoor unit EEPROM.
L17 Alarm
Alarm code L17
Alarm meaning Outdoor unit model mismatch
Alarm conditions This alarm occurs when a unit other than a R410A refrigerant model is connected.
Probable cause (1) A unit that uses R407C refrigerant, or a R22 model unit, was connected by mistake.
(2) The connected unit is correct, however the refrigerant type setting in the outdoor unit
EEPROM (item code 80) is incorrect.
Check (1) Check the refrigerant type at the connected unit.
(2) Use the outdoor unit maintenance remote controller and check the item code 80 refrigerant
type. If the setting is incorrect, change it to R410A.
Correction —
Example —
Notes The outdoor unit maintenance remote controller is required in order to set the refrigerant type in
the outdoor unit EEPROM.
L18 Alarm
Alarm code L18
Alarm meaning 4-way valve operation failure
Alarm conditions During heating operation (Comp. ON), the highest detected temperature at an outdoor unit
heat exchanger (EXG 1, EXG 2, EXL 1, or EXL 2) was 20°C or more above the outdoor air
temperature (Air Temp.) continuously for 5 minutes or longer, or the detected suction
temperature (SCT) was 20°C or more above the outdoor air temperature continuously for
5 minutes or longer.
Probable cause (1) The 4-way valve connector (20S CN20) has become disconnected from the control PCB.
(2) The 4-way valve circuit is locked (malfunctioning).
Check (1) Check the 4-way valve connector (20S CN20).
(2) If the connector is normal, check the 4-way valve wiring and the PCB circuit.
Correction If the connector is normal, correct or replace the problem locations.
Example —
Notes —
P02 Alarm
Alarm code P02
Alarm meaning Compressor thermal protector is activated. (trip only and no alarm)
When the current is not detected over 4 seconds long after the compressor ON.
Alarm conditions
Probable cause Activating condition of the compressor thermal protector (The voltage is more than 260V or
less than 160V between L and N phase.)
Check (1) Check the constant speed compressor.
(2) Check the current transformer.
Put the constant speed compressor OFF over 60 minutes and cool the thermostat.
Correction
Replace defective parts with new ones.
Example —
Notes —
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2WAY SYSTEM
Trouble Diagnosis
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