Gree GMVVQ1015WM/C-X, Руководство по обслуживанию

Страница: 141 / 433

Gree GMV6 HR DC Inverter VRF Units Service Manual
139
2.74 "E4" Protection in Case of Too High Air Discharge Temperature
of Compressor
Fault display: main board of outdoor unit, wired controller of indoor unit and receiver of indoor unit
display
Fault diagnosis:
When the compressor's discharge temperature detected by the temperature sensors on the
discharge pipes and on the top of the compressor is above 118°C, the unit stops running to ensure safe
operation.
Possible causes:
■ Check valve of the outdoor unit is closed;
■ The electronic expansion valve operates improperly;
■ Abnormal outdoor or indoor fans;
■ Clogging of indoor filter or air duct (cooling mode);
■ The ambient temperature where the unit operates exceeds the limi
t;
■ Insufficient refrigerant in the unit;
■ Clogging of unit pipes.
Troubleshooting:
Step 1: Inspect and make sure that the check valves of the gas pipe and liquid pipe of the outdoor
unit are fully opened.
Step 2: Power on the units based on the capacity and number of indoor units enabled previously in
the case of protection state. After confirming that the EXV coil is connected properly, power off the unit.
Then power on to reset the unit and check the resetting action. If unable to reset the unit, replace the coil
or the main board. If able to reset the unit normally, inspect other parts of the unit.
Step 3:
Power on the units based on the capacity and number of indoor units enabled previously in
the case of protection state. Observe whether the indoor and outdoor fans are operating properly
according to the rotational speed displayed by the commissioning software. If not, replace the motor or
motor drive module (outdoor fan).
Step 4: In the case of cooling mode, check whether the filter of the indoor unit is dirty or clogged or
whether the air resistance is too high (the air resistance is designed to be larger than the static pressure
of the unit as required).
Step 5:
Check whether the air return temperature of the unit exceeds the limit during operation
(requirements in cooling mode: outdoor ambient temperature -5°C to +50°C, indoor ambient temperature
16°C to 32°C; requirements in heating mode: outdoor ambient temperature -20°C to +24°C, indoor
ambient temperature 16°C to 30°C).
Step 6: Check whether the refrigerant is added in accordance with the design requirements, as
insufficient refrigerant may trigger system protection.
Step 7: Power on the units based on the capacity and number of indoor units enabled previously in
the case of protection state. Check whether the pipeline or expansion valve is blocked according to the
parameters of the indoor and outdoor units and the temperature of the pipelines (touch with hands).