Rheem mini split error code LF
Compressor over-speed protection.
- TypeProtection
- SystemCompressor / inverter
- Can I fix it?Technician job
- Applies toFloating Air series (Friedrich-built, Gree platform)
What LF means on a Rheem
The drive detected the compressor running faster than commanded and shut down.
On this platform, LF 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 failed inverter drive.
- A failing compressor.
- Unstable supply voltage.
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.
- 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.
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
Technician diagnosis of the drive.
Which Rheem units show LF
This page applies to Rheem Classic and Classic Plus wall-mount (RIWH / ROWH), Endeavor Line multi-zone and Floating Air series (2023 and later) units on the Floating Air series (Friedrich-built, Gree platform). Rheem's own documentation lists LF as "Compressor over-speed 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 Rheem shows this code
Floating Air series (Friedrich-built, Gree platform): 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 Rheem codes
Same part of the system as LF:
LF on other brands
The same characters do not always mean the same thing. Check the brand on your unit.
- Blueridge LF Compressor over-speed protection
Questions people ask
Can I reset a Rheem LF code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If LF comes back, the fault is real and needs the checks above.
Is it safe to keep running a Rheem showing LF?
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.
What will a technician check for LF?
Technician diagnosis of the drive. Ask for the measurements, not just a parts quote.
Sources
- Rheem RIWH / ROWH Ductless Design and Technical Manual (RIWH18ASJ to RIWH36AXJ)
- Rheem Classic Series ductless installation manual 9318739237 (Fujitsu General document number)
- Friedrich Floating Air Select 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.