Midea MCCDH30A-TA3SL, Technical & Service Manual

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Air-cooled modular chiller unit 50Hz
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Troubles Possible reasons Solutions
Compressor stops
because of integrate
temperature sensor or air
discharge temperature
protection.
Over high or over low voltage.
Confirm voltage not higher or lower than the rated
voltage 10%.
Over high air expelling pressure or excessive
low air suction pressure.
See “Over high air expelling pressure” and “excessive
low air suction pressure ”.
Component error.
Check the integrated temperature sensor after motor
is cool down.
Compressor stops
because of low pressure
protection.
Filter in front (or rear) of expanding valve is
blocked.
Replace a new filter.
Low voltage switch error. If the switch is defective, please replace a new one.
Excessive low air suction pressure. See “Excessive low air suction pressure”.
Abnormal noise comes
from compressor.
Liquid refrigerant flows into compressor from
evaporator result in liquid slugging.
Adjust refrigerant charge volume.
Aging of compressor. Replace a new compressor.
Compressor can‟t start.
Over current relay trip up, fuse burnt out. Replace damaged assembly.
Control circuit without power though. Check the wring of control system.
High voltage or low voltage protection.
Reference to mention in above the parts of air suction
and discharge pressure error.
Coils in contactor are burnt out. Replace damaged assembly.
Wrong connection of phase sequence.
Re-connect and adjust the any 2 wires among 3
phases.
Water system error and flow type volume
controller short connection.
Check water system.
Error signal delivered from wired controller.
Find out the error type and carry out the
corresponding measure to settle.
Air side heat exchanger
excessive frost.
4-way valve or thermal resistor error.
Check the running state. Replace a new one if
necessary.
Air loop short-circuit. Settle the short-circuit of air discharge.
With noise. Fixing screws at panel are loosen. Fix up all assemblies.