Midea Aqua Tempto Power Series, Manual

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MCAC-ATSM-2014-09 Aqua tempo power series tropical air-cooled scroll chiller 50Hz
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● Remove air from the system pipe with vacuum
pump. The vacuum pumping lasts for above 3 hours.
Confirm that the indication pressure in dial gauge is
within the specified scope.
● When the degree of vacuum is reached, inject
refrigerant into the refrigeration system with
refrigerant bottle. Appropriate amount of refrigerant
for injection has been indicated on the nameplate
and the table of main technical parameters.
Refrigerant must be injected from the low pressure
side of system.
● The injection amount of refrigerant will be affected
by the ambient temp.. If the required amount has not
been reached but no more injection can be done,
make the chilled water circulate and start up the unit
for injection. Make the low pressure switch
temporarily short circuit if necessary.
2) Refrigerant supplement. Connect refrigerant
injection
bottle on the fluoride nozzle at
low-pressure side and connect pressure gauge at
low pressure side.
● Make chilled water circulate and start up unit, and
make the low pressure control switch short circuit if
necessary.
● Inject refrigerant slowly into the system and check
suction and discharge pressure.
CAUTION
Connection must be renewed after injection is
completed.
Never inject oxygen, acetylene or other flammable
or poisonous gas to the refrigeration system at
leakage detection and air tight test. Only
pressurized nitrogen or refrigerant can be used.
1.6 Disassembling compressor
Follow the following procedures if compressor
needs to be disassembled:
1) Cut off the power supply of unit.
2) Remove power source connection wire of
compressor.
3) Remove suction and discharge pipes of
compressor.
4) Remove fastening screw of compressor.
5) Move the compressor.
1.7 Auxiliary electric heater
When the ambient temp. is lower than 2
℃
, the
heating efficiency decreases with the decline of the
outdoor temp.. In order to make the air-cooled heat
pump stably run in a relatively cold region and
supplement some heat lost due to de-frosting. When
the lowest ambient temp.
in the user’s region in
winter is within 0 C~10 C, the user may consider to
use auxiliary electric heater. Please refer to relevant
professionals for the power of auxiliary electric
heater.
1.8 System anti-freezing
In case of freezing at the water-side heat exchanger
interval channel, severe damage may be caused, i.e.
heat exchange may be broken and appears leakage.
This damage of frost crack is not within the warranty
scope, so attention must be paid to anti-freezing.
1) If the unit that is shutdown for standby is placed in
an environment where the outdoor temp. is lower
than 0
o
C, the water in the water system should be
drained.
2) Water pipe may be frozen when the chilled water
water flow switch and anti-freezing temp. senor
become ineffective at running, therefore, the water
flow switch must be connected in accordance with
the connection diagram.
3) Frost crack may happen to water-side heat
exchanger at maintenance when refrigerant is
injected to the unit or is discharged for repair. Pipe
freezing is likely to happen any time when the
pressure of refrigerant is below 0.4Mpa. Therefore,
the water in the heat exchanger must be kept
flowing or be toughly discharged.