HVACopedia

Kinghome · Heat pump

P6 Main-to-driver communication error

High severity Kinghome Ultranixx

What the control is telling you

The main board lost communication with the driver board for 30 s.

Applies to: Kinghome Ultranixx cold-climate KU36UHO and KU60UHO outdoor units with KU..UH2I and KD..UHI air handlers

Likely causes

  • Communication wire loose or broken
  • Drive board 3.3 V supply abnormal

Test and repair steps

  1. Warning: Switch off power at the breaker and wait for the DC bus capacitors to discharge before touching the outdoor control board or compressor wiring.
  2. Check the wire.
  3. Replace the driver or main board.

Models that show this code

6 models in Kinghome Ultranixx

KU24UH2IKU36UH2IKU36UHOKU48UH2IKU60UH2IKU60UHO

Other codes on the same units

  • H5 IPM module protection
  • H6 Fan motor feedback fault (indoor or outdoor)
  • H7 Compressor out-of-step
  • P0 Compressor minimum-frequency test / driver reset
  • P5 Compressor phase overcurrent
  • P7 Module temperature sensor circuit fault
  • P8 Power module over-temperature
  • EE Memory chip fault

Save it for the next call

Star this code in the HVACopedia app and keep the whole library on your phone for jobs with no signal.

Open the app

Source: Kinghome Ultranixx cold-climate KU36/60UHO service manual GC202306, sec. 3.3-3.4. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.