Trouble Shooting - Midea MAD020T1N1S1 Technical Manual

Midea Precision AC Technical Manual

8. Trouble shooting

When the system is suddenly having a demand, but there is a failure or invalidation which led to
non-workable, and then it cannot meet environmental needs. So it is necessary to periodically do the
functional test for the system components. Controller provides field manual opening and closing
function for all parts, and use for self-detecting the functional components' states of the system.
Detailed operations can be checked by system self-diagnostic function.
During the device operation, the internal unit may have a deadly high voltage. It only allow
specialized technical person to do the unit maintenance operation, and must be especially careful
during the troubleshooting with electricity.
 Common faults and handling methods of indoor fan
Symptom
Fan no
working
 Common faults and handling methods of dehumidification system
Symptom
No
dehumidification
effect
88
Probable reason
No main power supply
Overload, air switch is broken off
Contactor cannot contact together
Control panel error
Air flow lost switch alarm (activate)
Fan error.
System does not require carrying out dehumidification.
Contactor of compressor cannot contact together.
Compressor does not operate, the air switch broke off.
Dehumidification solenoid valve error
Check items or handling methods
Check the voltage between A, B, C.
Manual reset, check the average current value.
Check whether has 24V AC voltage between 28
and 03. (Wire numbers) If it has, then the
contactor has error, change it.
Check whether has 24V AC voltage between 28
and 03. If not, the control panel has error.
Check whether the belt has loosened or fan motor
has error, if not, then check whether the air flow
collecting plastic pip has abnormal position.
Replace it.
Probable reason
MCAC-PDSM-2013-01
Check items or handling methods
Check the control system status.
Refers to refrigerant
handling methods.
Check the air switch, contacting
points, check the air switch
voltage.
1, Check whether has 24V
voltage between wire 33 and wire
03.
2, Check whether reliable installs
the wires and valves.
system