Panasonic Aircon Error Codes

Reference table for common Panasonic codes. Use it to understand likely meaning, typical causes, and context before booking.

Before you use this tool

This is a guidance table, not a model-exact diagnosis. The same code can differ by series, controller, and model year. Use this page to narrow next steps, then verify with model sticker details.

Safety warning

Stop using the unit and contact a technician if the breaker trips repeatedly, you smell burning, see sparks, hear loud electrical buzzing, or water is leaking from places it normally should not.

Panasonic code table

Includes common SG residential split-system codes with likely meaning and typical causes.

E04Indoor

Indoor fan motor lock (model-specific)

Typical causes

Indoor fan motor locked or failing
Fan obstruction or seized bearing
Indoor fan-drive circuit/PCB abnormality

F11System

Cooling/heating cycle abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

F16Inverter

Total running current protection

Typical causes

Inverter IPM or power module abnormality
Compressor electrical overload or lock condition
DC bus voltage/current abnormality
Protection trip caused by sustained high load

F17System

Indoor standby units freezing abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

F18System

Indoor standby units overheating abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

F87Inverter

Control box overheating protection

Typical causes

Inverter IPM or power module abnormality
Compressor electrical overload or lock condition
DC bus voltage/current abnormality
Protection trip caused by sustained high load

F90Inverter

PFC protection circuit trip

Typical causes

PFC circuit protection triggered in outdoor inverter board
Power transistor/bridge components stressed or faulty
Voltage fluctuation or surge condition
Compressor/inverter load causing abnormal current draw

F91System

Refrigeration cycle abnormality

Typical causes

Refrigeration cycle abnormal due to leak or restriction
Expansion control issue affecting refrigerant flow
Compressor efficiency drop or overload
Sensor mismatch causing unstable control

F93Inverter

Compressor revolution abnormality

Typical causes

Inverter IPM or power module abnormality
Compressor electrical overload or lock condition
DC bus voltage/current abnormality
Protection trip caused by sustained high load

F94Outdoor

Compressor discharge pressure overshoot protection

Typical causes

Outdoor airflow restriction or dirty condenser coil
Outdoor fan motor/driver fault
Refrigerant pressure imbalance in circuit
Outdoor protection device triggered

F95Outdoor

Outdoor cooling high pressure protection

Typical causes

Outdoor cooling high-pressure protection triggered
Condenser airflow blocked or coil heavily soiled
Outdoor fan speed/fan motor issue
Refrigerant overcharge or non-condensable gas

F96Inverter

Power transistor module overheating protection

Typical causes

IPM/power module temperature exceeded limit
Inverter heatsink cooling degraded
High sustained compressor load
Outdoor PCB thermal management fault

F97Inverter

Compressor overheating protection

Typical causes

Compressor shell/discharge temperature too high
Low refrigerant or flow restriction
Compressor mechanical wear or high load
Insufficient condenser heat rejection

F98Inverter

Total running current protection

Typical causes

Total running current exceeded protection threshold
Compressor or fan electrical load abnormal
Power quality instability
Inverter control board fault

F99Inverter

Outdoor DC peak detection protection

Typical causes

Outdoor DC peak current detected by inverter protection
Compressor winding/drive abnormality
IPM/power stage stress under startup/load
Short-duration surge or fault on DC bus

H00System

No failure memory (no abnormality detected)

Typical causes

No active fault stored by self-diagnosis
Temporary symptom cleared after restart
Intermittent issue not currently detected

H11Communication

Indoor and outdoor communication abnormality

Typical causes

Loose or reversed interconnection cable between indoor and outdoor units
Corroded terminals or poor wire contact
Indoor PCB or outdoor PCB communication fault
Power instability after restart or blackout

H12System

Indoor unit capacity unmatched

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H14Sensor

Indoor intake air temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H15Sensor

Compressor temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H16Sensor

Outdoor current transformer abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H17Sensor

Outdoor intake air temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H19Indoor

Indoor fan motor mechanism lock

Typical causes

Indoor fan motor shaft locked or winding fault
Fan wheel jammed by dirt/debris
Indoor PCB fan-drive fault
Loose fan motor harness connection

H21Indoor

Indoor float switch operation abnormality

Typical causes

Condensate float switch activated by water level
Drain line blockage causing overflow
Drain pump malfunction (if equipped)
Float switch or wiring fault

H23Sensor

Indoor heat exchanger temperature sensor 1 abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H24Sensor

Indoor heat exchanger temperature sensor 2 abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H25System

Indoor ion device abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H26System

Minus ion generation abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H27Sensor

Outdoor air temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H28Sensor

Outdoor heat exchanger temperature sensor 1 abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H30Sensor

Outdoor discharge pipe temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H31Sensor

Evaporator outlet pipe temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H32Sensor

Outdoor heat exchanger temperature sensor 2 abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H33Communication

Indoor and outdoor misconnection abnormality

Typical causes

Loose or damaged interconnection cable between indoor and outdoor units
Poor terminal contact or corroded wiring joints
Indoor/outdoor PCB communication circuit fault
Power supply instability affecting data transmission

H34Sensor

Outdoor heat sink temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H35System

Indoor and outdoor water adverse current abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H36Sensor

Outdoor gas pipe temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H37Sensor

Outdoor liquid pipe temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H38System

Indoor and outdoor mismatch (brand code)

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H39System

Abnormal indoor operating unit or standby units

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H41System

Abnormal wiring or piping connection

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H50Indoor

Ventilation fan motor locked

Typical causes

Indoor fan, float switch, or drain path abnormality
Indoor PCB drive or control issue
Airflow restriction from clogged filter/coil
Water level/ice protection logic triggered

H51Indoor

Ventilation fan motor locked

Typical causes

Indoor fan, float switch, or drain path abnormality
Indoor PCB drive or control issue
Airflow restriction from clogged filter/coil
Water level/ice protection logic triggered

H52Indoor

Left-right limit switch fixing abnormality

Typical causes

Indoor fan, float switch, or drain path abnormality
Indoor PCB drive or control issue
Airflow restriction from clogged filter/coil
Water level/ice protection logic triggered

H58Sensor

Indoor gas sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H59Sensor

Eco sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H64Sensor

Outdoor high pressure sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H67System

nanoe abnormality

Typical causes

Indoor-outdoor model/capacity mismatch
Configuration or wiring/piping setup error
Refrigeration cycle instability
Protection logic triggered to prevent hardware damage

H70Sensor

Light sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H71Inverter

DC cooling fan inside control board abnormality

Typical causes

Inverter IPM or power module abnormality
Compressor electrical overload or lock condition
DC bus voltage/current abnormality
Protection trip caused by sustained high load

H72Sensor

Tank temperature sensor abnormality

Typical causes

Thermistor or sensor open/short circuit
Loose sensor connector or harness damage
Sensor drift from heat/moisture stress
PCB sensor input channel fault

H79Communication

Wireless LAN module write error

Typical causes

Loose or damaged interconnection cable between indoor and outdoor units
Poor terminal contact or corroded wiring joints
Indoor/outdoor PCB communication circuit fault
Power supply instability affecting data transmission

H85Communication

Abnormal communication between indoor unit and wireless LAN module

Typical causes

Loose or damaged interconnection cable between indoor and outdoor units
Poor terminal contact or corroded wiring joints
Indoor/outdoor PCB communication circuit fault
Power supply instability affecting data transmission

H97Outdoor

Outdoor fan motor mechanism lock

Typical causes

Outdoor fan motor lock or rotor resistance
Fan driver/output fault on outdoor PCB
Obstruction at outdoor fan section
High outdoor heat load stressing fan operation

H98Outdoor

Indoor high pressure protection

Typical causes

Refrigerant pressure too high in cooling cycle
Outdoor coil airflow blocked or condenser dirty
Outdoor fan underperforming
Refrigerant overcharge or restriction

H99Indoor

Indoor operating unit freeze protection

Typical causes

Indoor evaporator temperature dropped too low (freeze risk)
Dirty indoor filter/coil reducing airflow
Low refrigerant or sensor drift
Indoor fan performance issue

P10Outdoor

Outdoor high pressure protection (model-specific)

Typical causes

Outdoor high-pressure condition triggered protection
Condenser airflow restriction or dirty coil
Refrigerant overcharge or system pressure imbalance

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