Kaysun KEM-30 DNS3, Owners & Installation Manual

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c. 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.
d. The injection amount of refrigerant will be affected by the ambient
temperature. 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.
Refrigerant supplement. Connect refrigerant injection bottle on the
fluoride nozzle at low-pressure side and connect pressure gauge at
low pressure side.
a. Make chilled water circulate and start up unit, and make the low
pressure control switch short circuit if necessary.
b. Slowly inject refrigerant 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.
11.9 Disassembling compressor
Follow the following procedures if compressor needs to be
disassembled:
a. Cut off the power supply of unit.
b. Remove power source connection wire of compressor.
c. Remove suction and discharge pipes of compressor.
d. Remove fastening screw of compressor.
e. Move the compressor.
11.10 Auxiliary electric heater
When the ambient temperature is lower than 2°C, the heating
efficiency decreases with the decline of the outdoor temperature.
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 temperature 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.
11.11 Antifreezing
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 antifreezing.
a. If the unit that is shutdown for standby is placed in an
environment where the outdoor temperature is lower than 0°C,
the water in the water system should be drained.
b. Water pipe may be frozen when the chilled water target flow
controller and anti-freezing temperature senor become ineffective
at running, therefore, the target flow controller must be connected
in accordance with the connection diagram.
c. 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
thoroughly discharged.
11.12 Replacement of safety valve
Replace the safety valve as follows:
a. Reclaim the refrigerant completely in the system. Doing so
requires professional staff and equipment;
b. Note to protect the tank coating. Avoid damage to coating from
external force or high temperature when removing and installing
the safety valve;
c. Heat the sealant to screw off the safety valve. Note to protect
the area where the screwing tool meets the tank body and avoid
damages to the tank coating;
d. If tank coating is damaged, repaint the damaged area.
safety valve
Fig.11-1 Replacement of safety valve
WARNING
Safety valve warranty period is 24 months. Under the specified
conditions, if flexible sealing parts is used, the safety valve
life expectancy is 24 to 36 months, if metal or PIFE sealing
components is used, the average life expectancy is 36 to 48
months. Visual inspection is needed after that period, maintenance
people should check the appearance of the valve body and the
operating environment. If the valve body is not obvious corrosion,
cracks, dirt, damage, then the valve can be used continually.
Otherwise, please contact your supplier for spare part.