| Error Code |
What It Means |
Common Causes |
Common On: |
Homeowner-friendly Troubleshooting |
| CH0 |
Communication between the indoor and outdoor units has failed. |
‣ Loose or damaged wiring
‣ Faulty printed circuit board (PCB) in either the indoor unit or outdoor unit
‣ Power supply issues |
‣ Indoor AC units |
‣ Have the PCB inspected or replaced by a technician.
‣ Check the wiring between the indoor and outdoor units.
‣ Turn the unit off for 5-10 minutes before turning it back on to reset the communication. |
| CH05 / E0 / CH53 |
Indoor and outdoor units cannot communicate |
‣ Wiring issues
‣ Incorrect cabling
‣ Controller link fault |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Unplug the power cord or turn off the circuit breaker.
‣ Wait for 5 minutes.
‣ Restore power.
If the issue continues after the power cycle, call a licensed technician |
| CH93 |
Indoor and outdoor communication problem |
If the error was triggered after installation, it means the indoor and outdoor units are not stable or not receiving power. |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Inspect the power cord and other cable connections.
‣ Unplug the power cord or turn off the circuit breaker.
‣ Wait for 5 minutes, then restore power. |
| CH66 |
There is an issue with the communication line or piping connection between the indoor and outdoor units |
‣ If the error appeared immediately after installation, please contact a technician.
‣ If the error occurs during normal use, the error may be caused by a temporary fault because of an unstable power supply or other electrical factors. |
‣ Inverter-type |
‣ Unplug the power cord or switch off the circuit breaker.
‣ Wait for 5 minutes and then restore power. |
| CH1 |
The indoor temperature sensor is not working |
‣ Faulty temperature sensor
‣ Loose or damaged wiring
‣ Dirt or debris obstructing the sensor |
‣ Indoor AC units |
‣ Check the temperature sensor.
‣ Look for loose or damaged wiring connections.
‣ Call a technician to replace the faulty sensor. |
| CH2 |
Indoor humidity sensor is not detecting correctly |
‣ Malfunctioning or broken humidity sensor
‣ Loose or damaged wiring
‣ Dirt or debris on the sensor may interfere with the sensor’s ability to detect humidity |
‣ Indoor AC units |
‣ Contact a technician to replace the sensor.
‣ Make sure the wiring to the humidity sensor is secure and intact.
‣ Clean the sensor to remove dirt or debris |
| CH38 / F4 |
Sensor indicates low refrigerant |
‣ If an error occurs after installing or relocating the AC, the error is a sign of refrigerant shortage. This is best resolved by a professional.
‣ If the error occurs while using the AC, the issue may be temporary and caused by unstable power or other electrical factors |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Unplug the power cord or turn off the circuit breaker.
‣ Wait for 5 minutes and restore power. |
| CH3 |
Indoor fan motor has malfunctioned |
‣ Worn-out or faulty fan motor
‣ Dirt or debris blocking the fan
‣ Electrical wiring or power supply issues |
‣ Indoor AC units |
‣ Inspect the fan blades, test the fan motor.
‣ Make sure the wiring connections are secure and not damaged. |
| CH10 / E6 / CH67 / EF |
Indoor and outdoor unit fan issues |
‣ Debris accumulation
‣ Snow pile-ups
‣ Motor issues |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Clear any debris or snow buildup around the indoor and outdoor fan components.
‣ If there are no visible issues, professional service is required. |
| F0 |
High-pressure protection |
‣ Clogged coils or filters cause pressure to rise in the system
‣ Low refrigerant levels trigger high pressure
‣ Faulty pressure sensors that cause inaccurate readings |
‣ Outdoor AC units |
‣ Clean the coils and filters.
‣ Check and make sure the refrigerant levels are correct.
‣ Call a technician to check the pressure sensors for faults |
| F3 |
Low-pressure protection |
‣ Low refrigerant levels can cause the pressure to drop
‣ Refrigerant leaks
‣ Malfunctioning pressure sensors that send incorrect readings |
‣ Outdoor AC units |
‣ Check refrigerant levels and contact a technician to top up the refrigerant.
‣ Inspect for leaks.
‣ Let a technician test the pressure sensors for malfunctions. |
| F5 |
Compressor motor failure |
‣ Compressor motor failed or malfunctioned
‣ Excessive current or overload
‣ Loose or damaged wiring |
‣ Outdoor AC units |
‣ Check the motor for signs of malfunction.
‣ Make sure the wiring to the motor is intact.
‣ Call a technician to test the compressor. |
| CH04 / FL |
Drainage issues, malfunction of the indoor unit drain, or the condensate tank is too full |
‣ Full condensate tank
‣ Drain blockage |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Power off the appliance and unplug the power cord.
‣ Remove the drain cap
‣ Let the condensate drain into a bowl or pan.
‣ Securely screw the cap back on. |
| CH07 |
Standing and wall-mount AC units are set to different operating modes. (Conflicting modes) |
‣ Units set to different heating/cooling modes |
‣2-in-1 heating and cooling AC
‣ Ceiling-type |
‣ Check the operating mode of each AC unit.
‣ Set all to either heating or cooling/dehumidification. |
| CH54 |
Improper or incorrect power supply connection to the outdoor unit |
‣ Temporary power outage or electrical work |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Reset the air conditioner circuit breaker.
‣ If the error persists, call a professional technician immediately. |
| CH61 / P4 / P6 / P7 / P8 / CH34 |
The indoor or outdoor unit is overheating during cooling or heating |
‣ During cooling mode, the area around the outdoor unit is not well-ventilated, and it causes hot air to accumulate and raise the temperature.
‣ During heating mode, this error is caused by poor intake due to clogged or dirty air filters. |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Open a ventilation window.
‣ Clear any obstacles around the unit to ensure proper ventilation.
‣ Adjust the unit so it aligns with the ventilation window.
‣ Install an air guide to direct hot air from the outdoor unit to the outside environment.
‣ Clean the indoor unit filter.
‣ Perform a full power cycle reset. |
| CH90 / CH91/ F4 |
Displayed during the test run phase to prevent damage to the AC unit |
‣ If the error appeared after installing or relocating the unit, the piping connections should be checked by an installation technician.
‣ If the error occurred during normal use, it may be due to an unstable power supply or other electrical factors. |
‣ Ceiling-type
‣ Window-type
‣ Portable-type |
‣ Unplug the power cord or turn off the circuit breaker.
‣ Wait for 5 minutes, and then restore power. |
