Troubleshooting And Maintenance; Troubleshooting - McQuay MQS-174018-CFC216A Installation And Operation Manual

③. Cooling (heating) capacity stated above is measured under nominal working
conditions corresponding to standard external static pressure. The
parameters are subject to change with the improvement of products, in which
case the values on nameplate shall prevail.

8 Troubleshooting and Maintenance

8.1 Troubleshooting

If your air-conditioning unit suffers from abnormal operation or failure, please first
check the following points before repair:
Failure
The unit cannot be
started.
The unit operates for a
while
and then stops.
Poor cooling effect.
Poor heating effect
Note: After carrying out the check of the above items and taking relevant measures to
solve the problems found but the air-conditioning unit still does not function well, please
stop the operation of the unit immediately and contact the local service agency.
Only ask professional serviceman to check and repair the unit.
DC Inverter U-match Series Floor Ceiling Type Unit
Table 7.1
The power supply is not connected.
①.
Electrical leakage of air-conditioning unit causes tripping of the
②.
leakage switch.
The operating keys are locked.
③.
The control loop has failure.
④.
There is obstacle in front of the condenser.
①.
The control loop is abnormal.
②.
Cooling operation is selected when the outdoor ambient temperature
③.
is above 48°C.
The air filter is dirty or blocked.
①.
There is heat source or too many people inside the room.
②.
The door or window is open.
③.
There is obstacle at the air intake or outlet.
④.
The set temperature is too high.
⑤.
There is refrigerant leakage.
⑥.
The performance of room temperature sensor becomes worse
⑦.
The air filter is dirty or blocked.
①.
The door or window is not firmly closed.
②.
The set room temperature is too low.
③.
There is refrigerant leakage.
④.
The outdoor ambient temperature is lower than -5°C.
⑤.
Control loop is abnormal.
⑥.
Possible Reasons
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