Midea R410A Direct Heating Type HPWH 50Hz Technical Manual MCAC-HTSM-201906
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5 Maintenance
All the safety protection devices in the unit will be set before leaving the factory, the user can not adjust
or remove them, in case to damage the unit.
First switch on the unit or switch off the power for a long-term stop (More than 1 day) and then
re-power on, it should prior to connect to the supply from the compressor operation.
Please do not place other obstacles on the unit, it should keep dry and clean and well ventilated around
the unit. When the heat exchanger has dust, it should be immediately cleaned, in case to affect the unit
capacity or cause the unit stops for the protection.
Periodically clean the filter in the water system, for avoiding blocking and damage the unit or cause unit
protection, and it should ofter check the water replenishing system devices whether are normal.
When the ambient temperature is below zero, it is forbidden to cut off the power, otherwise, the
anti-freezing function will ineffective.
For long-time not use the unit, drain off the water in the unit and pipeline system, and open the water
plug on the water tank to drain off the water, incase the unit been frozen.
Please do not frequentyly on and off the unit, please do not manual cut-off the manual adjust valve
during the unit is operating.
Often check the working situation of each part in the unit, and check the inner pipe connectors of the
unit and whether the high and low pressure detecition ports of the refrigerant has oil dirty, to make sure
the unit has no refrigerant leakage.
Switch check for the electricity leakage protector.
The leakage flow protector of electric control box operates a period (Generally a month), should be in
the closed power on state to press the test button, check the leakage flow protector is normal or not
(each time press the button, the leakage flow protector should be broken off once), if it is not normal
and check the cause of the accident when be found, allowing once power on, and then, if no operation,
it should find out the reason of the fault, and if necessary, do the movement characteristic test; if it is
confirmed by the check for the leakage flow protector itself fails, it should be timely replacement or
repaired.
After running for a long time, the heat transfer surface of water side heat exchanger will deposit calcium
carbonate or other minerals, when these substances on the heat transfer surface scale is large, then can
affect the heat transfer performance and lead to increased power consumption, high air exhaust
pressure (or suction pressure is too low). It can use the organic acids such as formic acid, citric acid,
acetic acid detergent for cleaning. Do not use detergents containing fluoride chlorate, due to the
material of the water side heat exchanger is stainless steel or copper, which is easily to be corrosive and
cause refrigerant leakage.
Clean the water side heat exchanger should be conducted by professionals.
After using cleaning agent, use the clean water to clean the water pipe and heat exchanger, in case of
the waterproof system will be corrosive or has cleaning scale after adsorption.