Friedrich mini split error code P6
Communication error between inverter drive and main controller.
- TypeFault
- SystemCommunication
- Can I fix it?Technician job
What P6 means on a Friedrich
The compressor drive board and the outdoor main board stopped talking to each other.
On this platform, P6 is a fault: something has failed or is disconnected and needs diagnosis.
Common causes
- A loose connector between the boards.
- A failed drive or main board.
How to fix it yourself
Do the reset and the visual checks, but the underlying repair needs a technician with a meter and the service manual.
- Reset the system: switch the breaker (or the outdoor disconnect) off, wait a full five minutes so the boards fully discharge, then switch it back on and restart from the remote.
- With power off, reseat the connectors between the outdoor boards.
Switch off power at the breaker before opening either unit. Capacitors in the outdoor unit hold a charge for several minutes after power is cut.
When to call a technician
Board-level fault.
Which Friedrich units show P6
This page applies to Friedrich Floating Air Select (FSHW / FSHSW, 2015-2019), Floating Air Pro and Floating Air Premier units. Friedrich's own documentation lists P6 as "Communication error between inverter drive and main controller", the same definition used across the Gree platform it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.
Where Friedrich shows this code
The code shows on the indoor unit's display in place of the temperature. If the display is off, press the Light button on the remote. Some models also count out the code as indicator blinks. E codes are system protections and faults, F codes are mostly sensor faults, H codes are outdoor and compressor protections, U codes are motor and valve faults, and P codes are power-supply faults.
Other Friedrich codes
Same part of the system as P6:
P6 on other brands
The same characters do not always mean the same thing. Check the brand on your unit.
- Pioneer P6 Outdoor low pressure protection / Inverter module (IPM) malfunction (outdoor display)
- Blueridge P6 Communication error between inverter drive and main controller / Outdoor low pressure protection
- Gree P6 Communication error between inverter drive and main controller
- Zone Air P6 Cooling mode overheating protection
- Mitsubishi Electric P6 Freeze protection (cooling) or overheat protection (heating)
- Carrier P6 Outdoor low pressure protection
- Trane P6 Cooling mode overheating protection / Freeze protection (cooling) or overheat protection (heating)
- Heil P6 Outdoor low pressure protection / Communication error between inverter drive and main controller
- ACiQ P6 Outdoor low pressure protection / Cooling mode overheating protection
Questions people ask
Can I reset a Friedrich P6 code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If P6 comes back, the fault is real and needs the checks above.
Is it safe to keep running a Friedrich showing P6?
The unit will usually refuse to run, or run with reduced output, until the fault is cleared. Repeated resets do not fix anything and can mask a problem that is getting worse.
What will a technician check for P6?
Board-level fault. Ask for the measurements, not just a parts quote.
Sources
- Friedrich Floating Air Select Ductless Split System Service and Parts Manual (2015-2019), diagnostic code table
Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.