GREE         U-Match 5 SERIES UNIT SERVICE MANUAL 
60 
Possible reason
:
 
■Cut-off valve of ODU is not fully opened; 
■Electronic expansion valve is abnormal; 
■Outdoor or indoor fan is not working properly; 
■IDU filter or air duct is blocked (cooling mode); 
■Ambient temperature exceeds allowable operation range; 
■Refrigerant charging amount is insufficient; 
■System pipeline is blocked; 
Troubleshooting: