MCAC-PDSM-2013-04 Midea Precision AC Technical Manual-Down Delivery Series
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Common faults and handling methods of humidification system
Symptom
Probable reason
Check items or handling methods
No
humidification
effect
No water filling in the humidification tank
or low filling water pressure.
Check the water source.
Check the water inlet solenoid valve is open.
Check whether the water inlet pipe has blocked.
No humidification requirement.
Check manual operator.
No 24V AC input at controlling sire side of
humidification contactor.
Controller error.
Wiring from controller to the humidification
contactor controlling wire port is loose.
Common faults and handling methods of heating system
Symptom
Probable reason
Check items or handling methods
Heating system does not operates,
contactor do not contact together.
No heating requirement.
Check the controller status.
Heating temperature controller is
broken off and not reset.
1. Wait for the controller reset.
2. Change a new controller.
The contactor contacted together,
but no heating effect.
Heater error.
Turn off the power, check the
heating pipe and wire.
Common faults and handling methods of refrigeration system
Symptom
Probable reason
Check items or handling methods
Compressor
cannot run.
Power off. (Off the unit.)
Check the main power switch, fuse and
connecting wires.
Power overload and the air switch broke off.
Manual reset, check the current and air switch.
Electrical circuit connection is loose.
Fasten the connection.
Compressor wire circuit has burnt.
Check the compressor terminal.
The built-in protector of compressor has
broken off.
Check whether the compressor wire circuit is
open. If open, cool down the protector, then
automatically reset.
Symptom
Probable reason
Check items or handling methods
Compressor
cannot run.
Power off. (Off the unit.)
Check the main power switch, fuse and
connecting wires.
Power overload and the air switch broke off.
Manual reset, check the current and air switch.
Electrical circuit connection is loose.
Fasten the connection.
Compressor wire circuit has burnt.
Check the compressor terminal.
The built-in protector of compressor has
broken off.
Check whether the compressor wire circuit is
open. If open, cool down the protector, then
automatically reset.
The contactor cannot contact together. No
24V voltage input for the compressor control
wires. Or not reach the operating conditions
of compressor.
Check the manual operator parameters setting
correct or not. Check whether the controller is
error, or wiring from controller to compressor
port is loose.
