Friedrich mini split error code PH
DC bus high voltage (over-voltage) protection.
- TypeProtection
- SystemPower supply
- Can I fix it?Homeowner checks, then maybe a tech
What PH means on a Friedrich
The DC bus voltage inside the outdoor unit rose above its limit and the compressor stopped.
On this platform, PH is a protection: the system stopped or throttled itself to prevent damage; many clear on their own once conditions return to normal.
Common causes
- A utility voltage spike or a surge.
- A generator or inverter with poor regulation.
- A failed PFC stage or capacitor on the outdoor board.
How to fix it yourself
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician.
- 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.
- If you own a multimeter and are comfortable using it, measure the supply voltage at the outdoor unit's L1 and L2 terminals with the unit running. A 230 V system should read roughly 208 to 253 VAC.
- If your supply is prone to spikes, add a dedicated HVAC surge protector.
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
Normal supply voltage with a persistent PH means the outdoor board.
Which Friedrich units show PH
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 PH as "DC bus high voltage (over-voltage) protection", 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 PH:
PH on other brands
The same characters do not always mean the same thing. Check the brand on your unit.
- Blueridge PH DC bus high voltage (over-voltage) protection
Questions people ask
Can I reset a Friedrich PH code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If PH comes back, the fault is real and needs the checks above.
Is it safe to keep running a Friedrich showing PH?
Not repeatedly. A protection code means the unit stopped itself to prevent damage, and resetting it over and over can turn a cheap repair into a compressor failure. Reset once, check the basics, and stop if it returns.
Do I need a technician for Friedrich PH?
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician. Normal supply voltage with a persistent PH means the outdoor board.
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.