Ali ElmAC Error Codes
Panasonic air conditioners use a self-diagnostic system that displays error codes on the remote control, the indoor unit's LED panel, or through the Comfort Cloud app. These codes help identify exactly what has gone wrong, from minor sensor issues you can fix yourself through to serious compressor faults that need a qualified engineer.
This guide covers every Panasonic fault code across their residential and commercial range, including split systems, multi-splits, and VRF units. We have organised them by code series so you can find your specific error quickly.
How to Find the Error Code on Your Panasonic AC
There are three ways to retrieve the error code from your Panasonic unit:
Using the Remote Control
- Point the remote at the indoor unit.
- Use a paperclip or thin object to press the small "Check" button on the remote (usually recessed to prevent accidental presses).
- The display will show "- -" initially.
- Use the timer up/down buttons to scroll through any stored error codes.
- The unit will beep when a valid code is displayed.
Using the Comfort Cloud App
If your unit is connected to WiFi, open the Panasonic Comfort Cloud app and tap the notification icon in the upper left corner. Any active error codes will appear under the notifications tab with a description. You can download the app from Panasonic's Comfort Cloud page.
From the Indoor Unit LED
On some models, the timer and operation LEDs will flash in a pattern. Count the number of flashes to identify the code. Refer to your model's installation manual for the specific flash pattern chart.
H-Series Fault Codes: Hardware and System Faults
H-codes are the most common Panasonic error codes. They cover hardware faults including sensors, motors, drainage, and communication issues.
| Code | Meaning | What It Means in Practice |
|---|---|---|
| H00 | No fault detected | System is running normally. No action needed. |
| H11 | Indoor/outdoor communication failure | The indoor and outdoor units cannot communicate. Usually a wiring fault, loose terminal connection, or damaged control board. One of the most commonly searched Panasonic codes. |
| H12 | Indoor/outdoor capacity mismatch | The indoor unit does not match the outdoor unit's capacity rating. Common in multi-split systems where units are over-indexed or under-indexed. |
| H14 | Indoor air temperature sensor fault | The room temperature sensor is reading outside its normal range (above +46C or below -56C). Open or short circuit. Clean the sensor contacts and reseat the connector as a first step. |
| H15 | Compressor discharge temperature sensor fault | The sensor on the compressor discharge pipe has disconnected or failed. Located on the outdoor unit. |
| H16 | Low compressor current | The compressor is drawing less current than expected. Points to low refrigerant charge, a faulty current transformer, or a defective IPM (power) module. |
| H17 | Suction pipe temperature sensor fault | The sensor on the outdoor unit's suction pipe is open or short circuit. |
| H19 | Indoor fan motor locked | The fan motor speed does not match what the PCB is commanding. Could be a failed motor, a faulty PCB, or a physical obstruction blocking the fan blade. |
| H21 | Drainage blocked or float sensor fault | The condensate drain pan is full or the float switch is stuck. The drain pump may have failed. Clear the drain line and clean the float sensor as a first step. |
| H23 | Indoor heat exchanger sensor #1 fault | Sensor reading outside the -40C to +80C range. Open or short circuit. Clean the contacts and reseat the connector. |
| H24 | Indoor heat exchanger sensor #2 fault | Same as H23 but for the secondary sensor on dual-sensor models. |
| H25 | Ioniser (nanoe/e-ion) malfunction | The air purifying ioniser unit has failed or its control board is faulty. |
| H27 | Outdoor air temperature sensor fault | The outdoor ambient sensor is reading above +150C or below -40C. Disconnected or failed sensor. |
| H28 | Outdoor heat exchanger sensor fault | Temperature reading stuck at extreme values (+110C or -60C). Sensor disconnected or failed. |
| H30 | Compressor discharge temperature sensor fault | Readings above +200C or below -16C from the compressor-mounted sensor. |
| H33 | Wiring or voltage mismatch between units | Incorrect wiring between indoor and outdoor units, or a voltage mismatch on the data transmission line. |
| H34 | Power module heatsink sensor fault | The outdoor unit's power module radiator sensor is short or open circuit. |
| H35 | Drain pump malfunction | The condensate drain pump has failed or there is a blockage in the pump outlet. |
| H36 | Outdoor gas tube temperature sensor fault | The heating mode gas pipe sensor is reading outside normal range. |
| H37 | Outdoor liquid tube temperature sensor fault | The cooling mode liquid pipe sensor has an open or short circuit. |
| H38 | Indoor/outdoor unit mismatch | The units are from incompatible ranges or their internal brand codes do not match. |
| H39 | Indoor unit freeze protection (standby) | Solenoid valve malfunction or crossed refrigerant/control wiring. |
| H41 | Wiring error | Refrigerant pipes and control wiring are incorrectly connected. An installation error. |
| H50 | Indoor fan motor or board defective | The fan motor has failed or the indoor PCB that drives it is faulty. |
| H51 | Nozzle blockage | Physical blockage in the system nozzle. Requires disassembly to clear. |
| H64 | High pressure sensor failure | The high pressure sensor remains open for more than one minute when the compressor is off. |
| H67 | Nanoe X error | The Nanoe X air purification feature has malfunctioned. |
| H97 | Outdoor fan motor locked | The outdoor fan motor speed exceeds programmed limits. Check the motor, board, and connectors. |
| H98 | Indoor overheating protection (heating mode) | The heat exchanger temperature has risen above +52C. Often caused by dirty filters, blocked coils, or high indoor temperature. Clean the filters and coils first. |
| H99 | Indoor evaporator freeze protection | The evaporator coil is icing up, usually due to low refrigerant charge, dirty filters, or very low ambient temperature. Clean the filters first. If the coil keeps icing, you likely have a refrigerant issue. |
F-Series Fault Codes: Refrigeration Circuit and Compressor
F-codes relate to the refrigeration system, compressor, and power electronics. Most of these require a qualified engineer.
| Code | Meaning | What It Means in Practice |
|---|---|---|
| F11 | Four-way valve malfunction | The reversing valve that switches between heating and cooling has failed. The valve mechanism or its electromagnetic coil needs replacement. |
| F17 | Indoor unit freezing in standby | The evaporator is freezing while the unit is in standby mode. Solenoid valve leakage or incorrect sensor readings. |
| F90 | Compressor winding failure | Open circuit detected in the compressor windings. The compressor or inverter board needs replacement. |
| F91 | Refrigeration circuit fault (low pressure) | Low pressure protection has activated. Low refrigerant charge or a three-way valve failure. This is one of the most common Panasonic F-codes. |
| F93 | Compressor speed error | The compressor speed does not match the controller's commands. Compressor winding defect or inverter board failure. |
| F94 | High discharge pressure protection | Excessively high pressure in the refrigerant circuit. Check for condenser blockage, overcharge, or non-condensable gases. |
| F95 | Outdoor heat exchanger overheating | The outdoor coil is overheating during cooling mode. Usually caused by a dirty condenser coil or low refrigerant. Clean the outdoor coil as a first step. |
| F96 | Power module (IPM) overheating | The inverter power module is overheating due to contaminated heat exchanger or compressor failure. |
| F97 | High compressor discharge temperature | The compressor is overheating, usually from low refrigerant or a failing compressor. The unit may auto-reset after 20 minutes of cooling down. |
| F98 | Total current protection | The system is drawing too much current. Contaminated heat exchanger or refrigerant overcharge. |
| F99 | DC overcurrent protection | Compressor jam, transistor module failure, or low winding resistance. Requires immediate professional attention. |
E-Series Fault Codes: Communication and Electrical
E-codes deal with communication between system components and electrical faults. These are particularly common in multi-split and VRF installations.
| Code | Meaning | What It Means in Practice |
|---|---|---|
| E01 | Remote controller communication failure | The remote controller cannot communicate with the indoor unit. Check for obstructions, battery condition, and signal receiver. |
| E04 | Indoor unit receive failure / overcurrent | The indoor unit is not receiving data from the outdoor unit, or overcurrent protection has triggered. |
| E05 | Indoor unit transmit failure / PAM circuit fault | The indoor unit cannot send data to the outdoor unit. Power module circuit may have failed. |
| E06 | Outdoor unit receive failure / high compressor temp | The outdoor unit is not receiving signals from the indoor unit, or the compressor is overheating. |
| E07 | Outdoor unit transmit failure / indoor fan fault | Communication fault or indoor fan motor failure. |
| E09 | Multiple main remotes set / no refrigerant | Configuration error in multi-split systems, or the system has detected it is out of refrigerant. |
| E10 | DC compressor drive circuit failure | The inverter drive board has failed. Requires board replacement. |
| E11 | Signal output board failure / outdoor fan fault | Communication fault with the signal output board, or the outdoor fan has failed. |
| E13 | Transmit failure / freeze prevention active | Communication fault, or the unit has activated anti-freeze protection. Clean the filters and check airflow. |
| E16 | Auto-address alarm (too many units) | More indoor units detected than the system expects during automatic address configuration. |
| E21 | Outdoor main board failure | The outdoor unit's main PCB has failed. Requires board replacement. |
| E31 | General communication failure | Complete communication breakdown between system components. Check all wiring connections. |
P-Series Fault Codes: Power and Pressure
| Code | Meaning | What It Means in Practice |
|---|---|---|
| P01 | Indoor fan error | The indoor fan is not operating correctly. |
| P03 | High compressor discharge temperature | Compressor overheating. Similar to F97. |
| P04 | High pressure switch activated | Refrigerant pressure has exceeded the safety limit. |
| P05 | AC power supply fault | Incoming power supply issue. Check the breaker and supply voltage. |
What to Do When You See a Panasonic Error Code
Before calling an engineer, there are a few things worth trying:
- Write down the code - Note the exact error code displayed. If it is flashing or alternating between codes, write down the full sequence.
- Power cycle the unit - Switch the air conditioner off at the isolator (not just the remote), wait 60 seconds, then switch it back on. This clears temporary glitches caused by power fluctuations or sensor noise.
- Clean the filters - A surprising number of Panasonic error codes (H98, H99, E13, F95) are triggered by restricted airflow from dirty filters. Pull out the filters, wash them under running water, let them dry completely, and refit.
- Check the drain - If you see H21 or H35, the condensate drain is likely blocked. Clear the drain line with a vacuum or compressed air, and clean the drain pan.
- Check outdoor unit clearance - Make sure nothing is blocking airflow around the outdoor unit. Leaves, debris, or objects placed too close can trigger overheating codes like F95 and H98.
If the error code returns after these steps, or if the code relates to compressor, refrigerant, or electrical faults (F-series, most E-series), you need a qualified engineer.
When to Call a Professional
These categories of fault always need professional attention:
- Refrigerant-related codes (F91, F94, F97, H16, E09) - Under UK law, only F-Gas certified engineers can handle refrigerants. Topping up or recovering refrigerant without certification is illegal and dangerous.
- Compressor faults (F90, F93, F96, F98, F99) - These involve high-voltage components and specialist equipment. Do not attempt to diagnose or repair compressor issues yourself.
- Electrical and PCB faults (E10, E21, H33, H41) - Wiring errors and board failures carry electrocution risk. Switch the unit off at the isolator and wait for a qualified technician.
- Recurring codes - If the same error keeps coming back after a power cycle, there is an underlying issue that needs proper diagnosis with refrigerant gauges, electrical testing equipment, and manufacturer diagnostic tools.
UK Regulations for Panasonic AC Systems
If you operate a Panasonic air conditioning system in the UK, these regulations apply:
- F-Gas Regulation - Panasonic systems using R32 or R410A refrigerant require regular leak checks by certified engineers. The frequency depends on the system's CO2 equivalent charge. Full details are in the UK Government F-Gas guidance.
- TM44 Inspections - Systems with combined cooling capacity over 12kW must be inspected every five years by an accredited assessor. See the UK Government air conditioning inspections guidance.
- Building Regulations Part L - New installations must meet minimum SEER requirements. Current Panasonic inverter models comfortably exceed these thresholds.
Official Panasonic Resources
- Panasonic UK Heating and Cooling - Official UK product pages and support.
- Panasonic Comfort Cloud - Remote monitoring and error code notifications via the app.
- Panasonic Air Conditioning Europe - European product range and technical documentation.
Written by
Ali Elm
Ali is the Head of Operations at Be Cool Refrigeration with over a decade of hands-on experience in HVAC and commercial refrigeration. He oversees every installation, repair, and maintenance project, making sure the work meets the highest standards. Ali holds full F-Gas certification and has worked across residential, commercial, and industrial refrigeration systems throughout London and the South East. When he is not on site, he writes these guides to help business owners and homeowners understand their cooling systems better.