When a Gree mini split stops on a fault, the indoor unit’s display shows a two-character code instead of the temperature. This guide lists the Gree mini split error codes used on the models sold in the US, what each one means, which ones you can deal with yourself and what the usual repairs cost.
The definitions come from Gree’s own documents for North America: the GREE Comfort error code tool and FAQ, the installation manual for the Livo (LIVV) wall units and the service manual for Gree’s North American wall-mounted range. Some codes mean different things on different Gree models, so there is a section on those too.
Table of Contents
Check these three things first
Not every code on the display is a fault. Before you call anyone:
- H1 is normal. It means the unit is defrosting its outdoor coil in heating mode. The indoor fan pauses so it doesn’t blow cold air, and heating resumes on its own when the defrost ends. If it happens constantly and the outdoor unit is caked in ice, see our guide to a frozen heat pump.
- Fo (with a small o) is a status, not an error. Gree says it can appear while the unit is returning oil to the compressor or when a technician has put it into refrigerant pump-down mode.
- E7 on a multi-zone system means two indoor units are asking for different modes, one in Heat and another in Cool. Set every indoor unit to the same mode and the code clears.
If none of those apply, write down the code, then try the reset described further down. A code that comes straight back after a reset points to a real fault.
Gree mini split error codes: full list
These are the codes in Gree’s North American manuals for wall-mounted mini splits and their outdoor units. Older or non-US models can differ; see the next section.
Protection codes (E and F0)
| Code | What it means | Can you do anything? |
|---|---|---|
| E1 | High pressure protection | Yes, partly: clean the filters, clear the outdoor unit |
| E2 | Indoor coil anti-freeze protection | Yes, partly: clean or replace the filters |
| E3 | Low pressure protection | Clean the filters; a leak needs a technician |
| E4 | Compressor discharge temperature too high | Clear the outdoor unit; otherwise a technician |
| E5 | Overcurrent protection | Reset only; often a power supply problem |
| E6 | Communication fault between indoor and outdoor unit | Reset only; usually wiring |
| E7 | Mode conflict (multi-zone) | Yes: set all indoor units to the same mode |
| E8 | High temperature or overload protection, mostly in heating | Yes, partly: clean the filters and indoor coil |
| EE | Memory (EEPROM) fault on the control board | Reset only |
| F0 | Refrigerant leakage protection (low charge) | No, technician |
Sensor codes (F1 to F5, b5 and b7)
| Code | Which sensor is open or shorted | Can you do anything? |
|---|---|---|
| F1 | Indoor room temperature sensor | Reset only |
| F2 | Indoor coil temperature sensor | Reset only |
| F3 | Outdoor air temperature sensor | Look for damaged wiring outside |
| F4 | Outdoor coil temperature sensor | Reset only |
| F5 | Compressor discharge temperature sensor | Reset only |
| b5 | Outdoor liquid line sensor (multi-zone) | Reset only |
| b7 | Outdoor gas line sensor (multi-zone) | Reset only |
Gree notes that b5 and b7 often look like 65 and 67 on the display, which owners can mistake for a temperature. The giveaway is that the indoor unit won’t let you change the setting.
Fan, compressor and board codes (H, L, U and C)
| Code | What it means | Can you do anything? |
|---|---|---|
| H3 | Compressor overload switch opened (overheated) | Clear the outdoor unit and clean the filters |
| H4 | High temperature overload protection | Clean the filters and coils |
| H5 | Inverter power module (IPM) protection | Reset only |
| H6 | Indoor fan motor not reporting its speed | Reset only |
| H7 | Compressor out of step (desynchronized) | No, technician |
| HC | Power factor correction (PFC) protection | No, technician |
| L3 | Outdoor fan motor fault | With the power off, check nothing is jamming the fan |
| LC | Compressor failed to start | No, technician |
| LP | Indoor and outdoor units don’t match | No, installer |
| L9 | Power protection, often after a surge | Reset; call if it repeats |
| U1 | Compressor phase current detection fault | No, technician |
| U3 | DC bus voltage drop | Reset; have the supply checked |
| U4 | Reversing valve fault | No, technician |
| U8 / U9 | Zero-crossing detection fault on a control board | No, technician |
| C5 | Jumper cap or configuration fault | No, technician |
Codes that mean different things on different Gree units
Gree uses many control boards across its ranges, and a few codes have been reused. If the table above doesn’t match what your unit is doing, check the manual for your exact model number, which is on the label on the side of the indoor unit.
| Code | On US wall units | On some other Gree models |
|---|---|---|
| F0 | Refrigerant leakage protection | Indoor room sensor fault (some older and non-US units) |
| Fo | Status: oil return or pump-down | Easily confused with F0 on the display |
| U3 | DC bus voltage drop | Current detection fault (Livo installation manual) |
| U8 / U9 | Zero-crossing fault (indoor on some boards, outdoor on others) | Discharge sensor disconnected on some multi-split units |
| H6 | Indoor fan motor | Outdoor fan motor on Gree’s FLEXX ducted condensers |
| E8 | High temperature or overload protection | Indoor fan motor or board fault on some non-US units |
How to reset a Gree mini split
- Turn the unit off with the remote.
- Switch off the breaker or the outdoor disconnect. Gree’s FAQ says to leave the power off for 10 minutes.
- Turn the power back on and start the unit in the mode you need.
- Keep an eye on it for a while. Some codes only appear after the unit has been running for a few minutes.
If the remote itself is acting up, Gree suggests removing the batteries until the remote’s display goes blank, then putting them back. A reset clears a one-off glitch, for example after a power cut. It won’t fix a failed part, and resetting the same code over and over can hide a problem that gets more expensive the longer it runs.
The codes owners ask about most
E1: high pressure
The unit stopped because pressure on the hot side of the system got too high. Gree’s troubleshooting tool starts with the simple causes: dirty filters, a dirty indoor coil or blower wheel, and an outdoor unit that is dirty or boxed in so it can’t move air. On a new installation, Gree also lists service valves left closed, a system that wasn’t evacuated properly, and too much refrigerant. Clean the filters and clear leaves, snow or anything else blocking the outdoor unit. If E1 comes back, a technician needs to check the charge, the high-pressure switch and the expansion valve.
E6: communication fault
The indoor and outdoor units have stopped talking to each other. Gree gives a useful clue: if E6 shows as soon as the unit is powered up, the problem is most likely in the indoor unit; if it appears after three or four minutes, look at the outdoor unit. The usual causes are loose or mismatched connections on the 1, 2, 3 and ground terminals, the wrong cable type, a spliced cable, a poor ground, or a condensate pump wired into the communication line. Gree also notes that E6 won’t clear until the cause is fixed, so repeated resets won’t help.
H6: indoor fan motor
The control board isn’t getting feedback that the indoor fan is turning at the right speed. Gree’s checklist for technicians runs from the supply voltage and ground to spinning the blower wheel by hand to make sure nothing is binding it, then testing the motor and the board. For you, a reset is worth one try. If H6 returns, the fan motor or the indoor board usually needs replacing.
F0: refrigerant leakage protection
The system thinks it is low on refrigerant and shuts down to protect the compressor. Refrigerant isn’t used up in normal operation, so a low charge means a leak somewhere. Gree’s procedure is to recover and weigh the charge, find and repair the leak, pull a deep vacuum and weigh in the correct amount. Topping up without finding the leak only buys time.
H5: IPM protection
H5 means the inverter’s power module protected itself. It sounds like a board failure, but Gree points out that many things can cause it before any part has failed: dirty coils, poor airflow, closed service valves or the wrong refrigerant charge. A technician should rule those out and test the compressor windings before replacing the inverter board.
For other brands, see our guides to Mitsubishi, LG and Fujitsu mini split error codes.
What Gree repairs usually cost
| Repair | Typical cost |
|---|---|
| Cleaning filters, clearing the outdoor unit | $0 |
| Diagnostic visit | $60–$200 |
| Fan motor (indoor or outdoor) | $200–$700 |
| Control board | $150–$700 |
| Reversing valve | $200–$650 |
| Refrigerant leak repair | $300–$1,200 |
| Compressor | $650–$2,400 (up to $4,500 on some mini splits) |
Ranges come from Angi’s heat pump repair data and PickHVAC’s mini split repair cost guide (both May 2026). If the part is under warranty, you mostly pay for labor.
Is it covered by the warranty?
Gree’s FAQ says its warranty runs from 1 to 10 years depending on the part and on who installed the system, and that systems must be installed by an HVAC contractor in line with local and national codes. Registration is done online and applies to US products. Check your registration before you pay for a part, and ask the technician to note the error code on the invoice.
Frequently asked questions
Where do I see the error code on a Gree mini split?
On the indoor unit’s display, where the temperature normally shows. Many outdoor units also have status lights on the main board that a technician can read.
Is H1 an error on a Gree mini split?
No. H1 means the unit is defrosting in heating mode. It clears by itself.
What is the difference between F0 and Fo?
On US wall units, F0 (zero) is refrigerant leakage protection, which needs a technician. Fo (small o) is a status code shown during oil return or refrigerant pump-down.
How do I reset a Gree mini split?
Turn it off, switch off the breaker for 10 minutes, then turn it back on. If the same code returns, the fault is real.
Why does my Gree show 65 or 67?
On a multi-zone system, that is probably b5 or b7, a fault on one of the outdoor unit’s pipe sensors, not a temperature.
Seen a Gree code that isn’t on this list, or a fix that worked for you? Leave a comment below.
Sources
- GREE Comfort, Error Code Tool for GREE Systems
- GREE Comfort, FAQs
- GREE Comfort, Understanding GREE Mini-Split Error Codes (January 2024)
- Gree, Liv heat pump high-wall installation manual, LIVV09HP230V1A to LIVV36HP230V1A (2019)
- Gree, wall-mounted air conditioner service manual (North America)
- Angi, Heat Pump Repair Cost (May 2026)
- PickHVAC, Mini Split Running, Service and Repair Cost (May 2026)