Gree Heat Pump Error Codes

Updated October 13, 2026 · by Aurora Star Tech Inc.

125 Gree Heat Pump error codes and diagnostic codes, with causes and troubleshooting steps for each. Select a code, or find your model below.

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Gree Heat Pump error codes list

Code	Meaning	Severity
A0	Waiting for commissioning (status)	Low
Ab	Emergency stop	Medium
AU	Remote emergency stop	Low
b1	Outdoor ambient sensor open or shorted (15K)	Medium
b2	Defrost (coil) sensor open or shorted (20K)	Medium
b4	Sub-cooler liquid outlet sensor open or shorted (20K)	Medium
b5	Liquid line (valve) temperature sensor open or shorted	Medium
b6	Accumulator inlet sensor open or shorted (20K)	Medium
b7	Gas line (valve) temperature sensor open or shorted	Medium
bd	Sub-cooler gas inlet sensor open or shorted (20K)	Medium
bH	System clock abnormal	Low
bJ	High and low pressure sensors swapped	Medium
C0	Communication fault IDU/ODU/wired controller	High
C1	Main board to DC-DC controller communication fault	High
C2	Main board to compressor drive communication fault	High
C3	Main board to fan drive communication fault	High
C4	Missing indoor units	High
C5	Jumper (capacity) cap missing or bad	Medium
CH	Indoor capacity too high	Medium
CL	Indoor capacity too low	Medium
CP	More than one master wired controller	Low
d1	Indoor main board fault	High
d3	Indoor return air sensor open or shorted (15K)	Medium
d4	Indoor coil inlet pipe sensor open or shorted (20K)	Medium
d5	Indoor coil middle pipe sensor open or shorted (20K)	Medium
d6	Indoor coil outlet pipe sensor open or shorted (20K)	Medium
d9	Indoor jumper cap fault	Medium
dC	Indoor capacity DIP setting wrong	Medium
dd	Wiring/EEV check running (status)	Low
dH	Wired controller board fault	Low
dL	Indoor discharge air sensor open or shorted (15K)	Medium
dn	Wrong interconnect wiring or EEV fault	Medium
E0	Outdoor unit fault (shown with another code)	Medium
E1	High pressure protection	High
E2	Indoor coil freeze protection (status)	Low
E3	Low pressure protection	High
E4	Compressor discharge temperature too high	High
E5	Overcurrent protection (whole unit)	High
E6	Indoor/outdoor communication fault	High
E7	Mode conflict between indoor units (status)	Low
E8	High temperature / overload protection	Medium
E9	Cold air prevention (status)	Low
Ed	Drive IPM low temperature protection	Medium
EE	EEPROM / memory chip fault	High
EU	Compressor slowed - module running hot	Low
F0	Low refrigerant / refrigerant blocked protection	High
F1	Indoor room air sensor open or shorted	Medium
F2	Indoor coil sensor open or shorted	Medium
F3	Outdoor ambient sensor open or shorted	Medium
F4	Outdoor coil (condenser middle) sensor open or shorted	Medium
F5	Compressor discharge sensor open or shorted	Medium
F6	Compressor slowed - overload	Low
F8	Compressor slowed - high current	Low
F9	Compressor slowed - high discharge temperature	Low
FH	Compressor slowed - indoor coil anti-freeze	Low
Fo	Refrigerant recovery (pump-down) mode	Low
FP	Outdoor DC fan motor fault	High
H0	Compressor slowed - high indoor coil temp in heating	Low
H1	Defrost or oil return (status)	Low
H3	Compressor overload protection	High
H4	System abnormal (overload)	Medium
H5	IPM (inverter module) protection	High
H6	Indoor fan motor not running / no feedback	High
H7	Compressor lost synchronism	High
H8	Fan drive module overheated	High
H9	Inverter fan lost synchronism	High
HA	Fan drive memory chip fault	High
HC	PFC protection	High
HE	Inverter fan phase loss	High
HF	Fan drive charging circuit fault	High
HH	Fan drive DC bus voltage too high	High
HJ	Inverter fan failed to start	High
HL	Fan drive DC bus voltage too low	High
HP	Inverter fan AC current protection	High
HU	Fan drive AC input voltage fault	High
J1	Compressor overcurrent	High
J7	4-way valve gas mixing	High
J8	High pressure ratio protection	Medium
J9	Low pressure ratio protection	Medium
JA	Abnormal pressure protection	High
JF	WiFi module fault	Low
JL	High pressure too low	High
L0	Indoor unit fault	Medium
L1	Indoor fan protection	High
L3	Outdoor DC fan motor fault	High
L4	Wired controller power fault	Low
L5	Indoor freeze protection	Low
L6	Mode conflict (24 V adapter systems)	Low
L7	No master indoor unit	Medium
L8	Indoor power insufficient	Medium
L9	Power protection	Medium
LA	Group control: indoor series mismatch	Low
Lb	Group control: units from different systems	Low
LC	Compressor failed to start	High
Ld	Compressor phase loss	High
LJ	Indoor function DIP setting wrong	Medium
LP	Indoor and outdoor units do not match	Medium
LU	PG fan motor zero-crossing fault	Medium
oE	Undefined outdoor unit error	Medium
P4	Compressor drive PFC protection	High
P5	Compressor phase overcurrent	High
P6	Compressor drive IPM protection	High
P7	Inverter module temperature sensor fault	Medium
P8	Inverter module overheated	High
P9	Inverter compressor lost synchronism	High
PA	Compressor drive memory chip fault	High
PC	Compressor drive current sensing fault	High
PE	Inverter compressor phase loss	High
PF	Compressor drive charging circuit fault	High
PH	DC bus voltage too high	High
PJ	Inverter compressor failed to start	High
PL	DC bus voltage too low	High
PP	Inverter compressor AC current protection	High
PU	DC bus capacitor charging fault	High
U0	Compressor preheat not finished	Low
U1	Compressor phase current sensing fault	High
U2	Outdoor capacity code / jumper wrong	Medium
U3	DC bus voltage drop	Medium
U4	Refrigerant shortage at startup	High
U5	Whole-unit current sensing fault	High
U6	Service valves not opened	Medium
U7	Reversing (4-way) valve fault	High
U8	Indoor zero-crossing signal fault	Medium
U9	Outdoor zero-crossing fault	High
UE	Refrigerant charging invalid	Medium

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General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.

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