Home › Air Conditioners › Daikin › F6
Daikin Air Conditioner F6 Error Code
High pressure in cooling mode. Here is what it means and how to clear it, easiest fix first.
The system shut down to protect itself because refrigerant pressure rose too high while cooling. Daikin lists an overcharged system, a disconnected temperature sensor or an outdoor board fault as causes. Poor airflow through the outdoor coil makes high pressure more likely.
Daikin uses this code across its residential split, SkyAir and VRV ranges, but the exact meaning and causes can vary by series, model year and region, so confirm it in your unit's manual. How to read it: most Daikin ductless wall units only blink the operation lamp. On remotes such as the ARC433 series, press and hold the timer Cancel button for roughly 5 seconds until 00 blinks on the screen, then press Cancel again one step at a time; when the indoor unit answers with a long continuous beep, the code showing is the stored fault. SkyAir and VRV wireless remotes use a different sequence with the Inspection/Test, up/down and MODE buttons, and wired wall controllers usually show the code on their screen.
How to fix Daikin F6
Clear around the outdoor unit
With the breaker off, remove leaves, grass clippings, snow or anything stored against the outdoor unit, and keep about 2 ft (60 cm) clear on all sides. Brush loose debris off the outside of the coil fins by hand or with a soft brush; do not use a pressure washer or bend the fins. Give the outdoor coil the best airflow you can before restarting.
Reset the power at the breaker
Switch the system off with the remote, then turn off its circuit breaker in your home's main panel. Wait about 5 minutes, switch the breaker back on and restart the unit. If the code returns within a few minutes, write it down for the technician.
When to call a technician
If F6 comes back, call an HVAC technician to check the charge, sensors and outdoor fan.
Parts that commonly cause F6
- outdoor heat exchanger thermistor
- outdoor control board
Order parts by your exact model number so they fit.
Other Daikin air conditioner codes
- U4Indoor and outdoor units can't communicate
- U0Low refrigerant or restricted refrigerant flow
- U2Power supply voltage problem
- UAIndoor and outdoor units don't match
- A1Indoor unit control board fault
- A3Condensate water level too high
- A5Freeze-up or overheat protection
- A6Indoor fan motor fault
- C4Indoor coil temperature sensor fault
- C9Indoor room air temperature sensor fault
- E1Outdoor unit control board fault
- E5Compressor overload or lock-up protection
- E6Compressor won't start
- E7Outdoor fan motor fault
- E8Compressor current too high
- F3Compressor discharge temperature too high
- H6Compressor position sensing error
- L4Inverter heat sink overheating
- L5Inverter output overcurrent
Frequently asked questions
What does F6 mean on a Daikin air conditioner?
The system shut down to protect itself because refrigerant pressure rose too high while cooling. Daikin lists an overcharged system, a disconnected temperature sensor or an outdoor board fault as causes. Poor airflow through the outdoor coil makes high pressure more likely.
Can I fix Daikin F6 myself?
Only the basic checks. You can safely try the steps above, but F6 usually points to a part or fault that needs a technician.
What if F6 keeps coming back?
A code that returns after a reset and the checks above usually means a part is wearing out. Note when F6 appears (which cycle, how often) and have your model number ready; it helps a technician bring the right part on the first visit.
Last reviewed 2026-10-19. Codes and steps can vary by model; check your owner's manual.