(4) Tighten all connectors.
(5) Take the leakage test for all piping. If leakage occurs, eliminate it.
(6) Regulate the water flow through the balance valve and check the water pressure.
(7) Check if the oil circulation goes properly through the sight glass located on the compressor.
(8) Check if the fan rotates properly.
(9) Check if the system vibration and noise are acceptable.
7.7 Parts Replacement
Only parts supplied by Gree can be replaced instead of similar parts supplied by others.
7.8 Refrigerant Charging
Refrigerant charging should be done based on the discharge and suction pressure. An air tight test
must be taken on the condition refrigerant leaks or some part is required to be replaced. Refrigerant
charging comes into two cases stated below.
Complete charging
◆
In this case, take a leakage test by charging hi-pressure nitrogen (15~20kg) or refrigerant into
the system. If soldering is required, note that gas inside the system must be expelled firstly. The
whole system must be dried and vacuumed prior to charging.
(1) Connect the manifold gauge.
(2) Vacuum the system with the vacuum pump.
(3) After the system pressure reaches the required value (<80Pa) for more than 30 minutes
and keeps below 100Pa, charge refrigerant at the low pressure side as per the rated
specification on the nameplate.
(4) Refrigerant charge will be affected by the ambient temperature. When charged refrigerant
is under the required amount, add in accordance with the other charging case stated below.
Adding
◆
Connect the refrigerant charging port at the lower pressure side to the refrigerant tank and
install a manifold gage.
(1) Circuit the chilled water and start up the unit.
(2) Charge refrigerant vapor into the system slowly and check the suction and discharge
pressure.
WARNING!
When performing the leakage and air tight test, never charge oxygen, acetylene and other
flammable and toxic gases but only hi-pressure air, nitrogen or refrigerant.
Mineral scale on the surface of the heat exchanger will affect the heat exchanging efficiency
and increase the water resistance and lower the refrigeration capacity. Therefore, it should be
cleared away through dilute acid. Note that contents of different water quality vary and should be
treated with different type of acid by the qualified chemical company.
7.9 Removal of the Compressor
Please take the steps below when the compressor is required to be removed.
(1) Cut off the power supply.
(2) Recover the refrigerant in a reasonable speed to prevent oil from being drawn out.
(3) Remove the power cord and the temperature sensor.
Copyright 2018. This translation is property of GREE PRODUCTS SL. All rights reserved. Total or partial reproduction without its express authorization is prohibited.
D Series Modular Air-cooled Scroll Chillers Owner's Manual
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