Gree Mini Split Error Codes: E6, F0, H5, H6 and More

By Ray Bennett · Updated 2 October 2026 · 7 min read · Checked against the maker’s manual

Gree Mini Split Error Codes: E6, F0, H5, H6 and More

Short answer

A Gree shows its code by blinking it in place of the temperature. E6 means the indoor and outdoor units are not talking, most often from the wrong wire or a splice, F0 is refrigerant leakage protection, H6 is the indoor fan motor and H5 the compressor's power module. E2, E9 and H1 are not faults at all, and E7 is two rooms asking for different modes.

When a Gree mini split finds a problem, the temperature display on the indoor unit blinks a code instead of the temperature. Some codes are the unit telling you what it is doing, one is a setting you can fix with the remote, and the rest point at a part.

Everything on this page comes from Gree Comfort, Gree’s own US site: its guide to mini split error codes, its E6 troubleshooting guide, its F0 diagnosis guide, the owner’s manual for the Vireo Gen3 and the service manual for the Sapphire. Codes are shared across Gree’s range, but your own model’s manual has the final word.

Before you start

What to carry: a torch and a pen. Ten minutes.

Gas or electric? A mini split is all electric, a heat pump that heats and cools.

Write the code down. Note whether it came up at once or after a few minutes of running. For E6, Gree says the timing tells a technician which unit to look at first.

Try one restart. Gree’s owner’s manual says that for U8, H6, H3, E1, E5, E6 and E8, you can try restarting the unit, and call a qualified technician if that does not correct it.

When Gree says to switch off and call. Power off and call the installer or a licensed technician if the power wiring is overheating or damaged, there is an abnormal sound, the breaker trips often, there is a burning smell or the indoor unit is leaking. Gree’s manual says not to try to service or repair the unit yourself.

Refrigerant and power module codes are licensed work. Gree’s guide says codes such as E3 and F0 need a technician to check the charge and find leaks, and H5 needs service.

Codes that are not faults

E2, E9 and H1 are status codes, the unit protecting itself during normal running. E7 is the one you fix with the remote.

Check 1Free, one minute

Rule these out first

E2: anti-freezing protection. Gree’s manual says it is not an error code but a status code. The unit is protecting the indoor coil from icing in cooling.

E9: cold air prevention. Also a status code. In heating the unit waits until its coil is warm before it blows, so you do not get a blast of cold air: what a mini split does on heat that looks like a fault.

H1: defrost. Gree calls it a status code. The outdoor unit is clearing frost, and heating returns by itself.

E7: mode conflict. On a multi zone system, one room is set to cool and another to heat. Gree says to make sure all the indoor units run on cool, or all on heat. Gree’s guide calls this something a homeowner can often handle alone.

What each code means

These come from the error code table in Gree’s Sapphire service manual, with the causes Gree lists.

Code	What Gree says it means	Causes Gree lists
E1	High pressure protection	Too much refrigerant, poor heat exchange, very high outdoor temperature
E3	Low pressure	Dirty filters and coils, then the charge and leaks
E4	Compressor discharge temperature too high	Discharge protection or overload
E5	Overcurrent protection	Unstable or low supply voltage, a high load, a dirty evaporator
E6	Indoor and outdoor units not communicating	The wire between the units, most often
E8	High temperature protection	Overload or high temperature
EE	Outdoor board memory (EEPROM)	The outdoor control board
F0	Refrigerant leakage protection	A leak, the indoor coil sensor, a blockage
F1	Indoor room temperature sensor	The sensor, its plug, the board
F2	Indoor coil temperature sensor	The sensor, its plug, the board
F3	Outdoor air temperature sensor	The sensor or its connection
F4	Outdoor coil temperature sensor	The sensor or its connection
F5	Discharge temperature sensor	The sensor, or it is not in its tube
FH	Slowing down to stop the coil freezing	Poor return air indoors, fan speed too low
H3	Compressor overload protection	A loose overload terminal, discharge or overload faults
H4	System abnormal	Overload or high temperature
H5	Power module (IPM) protection	The module, the compressor, voltage
H6	Indoor fan motor not running	The motor, its plugs, a stalled fan, the board
H7	Compressor out of step	The compressor or its drive
HC	PFC protection	The outdoor control board or reactor
L3	Outdoor fan motor	The motor, a blocked system, a loose plug
L9	Power protection	High power draw; restarts after 3 minutes
LP	Indoor and outdoor units do not match	The wrong pairing
PH	DC voltage too high	Supply voltage above 265 volts
PL	DC voltage too low	Low supply voltage
U3	DC voltage dropping	Unstable supply voltage
U7	Four way valve abnormal	Supply under 175 volts, the valve or its wiring
U8	The whole unit stops	The power supply, the indoor board’s detection circuit
C5	Jumper cap protection	No jumper cap, a wrong or damaged one

E6: indoor or outdoor, by when it shows

Gree's rule of thumb: E6 at power on points at the indoor unit, E6 after three or four minutes points at the outdoor unit.

Check 2

What Gree says about E6

It is not usually the board. Gree says an E6 does not automatically mean the outdoor main board needs replacing, and to investigate the wiring first.

The number one cause. Gree says a wrong wire or a wire splice causes communication failures more often than any faulty part. The specified cable is 14 gauge, 4 conductor stranded wire rated 600 volts.

Check the whole run. Gree says to inspect the entire cable between the units, not just the ends, and that 1, 2, 3 and ground must match at both units.

The timing. If E6 shows the moment the system powers on, Gree says start at the indoor unit. If it takes 3 to 4 minutes, start at the outdoor unit.

What you can do. Look at the cable where you can see it for damage, a splice or a chewed section, and tell the technician when the code appeared. Testing the terminals is meter work at full voltage.

The checks that are yours

Check 3Free, twenty minutes

Work the owner checks, power off first

E1 and E3: the filters. Gree’s guide says homeowners can check for dirty filters, and call a qualified technician if they are clean: how to wash mini split filters.

E1: the outdoor unit’s air. Gree lists poor heat exchange and a bad radiating environment. Clear anything crowding the outdoor unit and rinse a matted coil: how to rinse an outdoor coil without bending the fins.

FH: the return air. Gree lists poor return air at the indoor unit or a fan speed that is too low. Clean the filters, keep furniture away from the unit and raise the fan speed.

E7: the modes. Every room on cool, or every room on heat.

One restart. For U8, H6, H3, E1, E5, E6 and E8, Gree’s manual says a restart is worth trying before calling. L9 restarts itself after 3 minutes.

When it needs a technician

Check 4

Know when to stop

F0 and E3. Refrigerant leakage protection and low pressure. Gree’s guide says a technician should weigh the charge and check for leaks: signs the refrigerant is leaking.

H5, H7, H3 and LC. The compressor and its power module. Gree says H5 needs service.

The F sensor codes. Gree says sensor faults usually need the part replaced by a skilled technician, after checking its connection.

PH, PL, U3 and U7. Supply voltage problems. Gree’s manual gives the thresholds a technician measures against, and an electrician may need to look at the supply.

C5. Gree says that after a control board is replaced, the jumper from the old board must move to the new one.

Questions people ask

What does E6 mean on a Gree mini split?

The indoor and outdoor units are not communicating. Gree says the most common cause is the wrong wire or a splice in the cable between them, not a failed board.

What does F0 mean on a Gree?

Refrigerant leakage protection. Gree lists a refrigerant leak, a faulty indoor coil sensor or a blockage. It needs a technician to check the charge and look for leaks.

What is H6 on a Gree mini split?

The indoor fan motor is not running. Gree lists poor contact at the motor’s plugs, a stalled fan, a failed motor or the board. Try one restart, then call a technician.

What does H5 mean?

The compressor’s power module has gone into protection. Gree says it needs service.

My Gree shows E9 or E2. Is it broken?

No. Gree’s manual says these are status codes, not error codes. E9 is the unit warming up before it blows in heating, and E2 is protecting the indoor coil from freezing.

What does E1 mean on a Gree?

High pressure protection. Gree lists too much refrigerant, poor heat exchange and very high outdoor temperatures. Check the filters and the outdoor unit’s airflow first.

Sources: Gree Comfort: mini-split error code guide, E6 troubleshooting guide, F0 diagnosis guide (May 2026), Vireo Gen3 owner's manual and Sapphire service manual