GREE              Duct type Ducted Type Split Air-Conditioner Units 
99 
Troubleshooting: 
1)  Replace the small CPU board. 
2)  Replace the control board. 
3)  Replace the control board. 
(29)   “F5” malfunction of discharge temperature sensor for compressor 1 
Error display: the main board of outdoor unit and indoor unit will display  . 
Applicable model: all outdoor units. 
Error judgment condition and method
:Sample the AD value of temperature sensor through 
temperature sensor detecting circuit and judge the range of AD value, if the sampling AD value exceeds 
upper limit and lower limit in 30 seconds continuously, report the error. 
Possible reason
: 
1)  Poor contact between discharge temperature sensor and terminal in mainboard interface. 
2)  The discharge temperature sensor is abnormal. 
3)  The detected circuit is abnormal. 
Troubleshooting
: 
Yes
“F5” discharge 
temperature sensor error 
of compressor 1
Re-insert it after proper 
treatment
The detected circuit might 
be abnormal
Yes
Replace the main control 
board
No
Check the wiring terminal of the main board 
and temperature sensor to see if it’s loose or 
are there any foreign objects
No
Replace the temperature sensor
 
(30)   “J7” air-mixing protection for 4-way valve 
Error display: the main board of outdoor unit and indoor unit will display  . 
Applicable model: heat pump models. 
Error judgment condition and method
:Detect system high and low pressure through pressure 
sensor, start the unit, when the pressure difference of high and low pressure is less than 0.1MPa, the 
unit will be stopped for protection. 
Possible reason: 
1)  Coil or connection wire is abnormal.