D Series Modular Air-cooled Scroll Chillers 
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(3) Check the water pump.
(4) Tighten all connectors.
(5) Take the leakage test for all piping. If leakage occurs, eliminate it. 
(6) Regulate the water ow 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 rstly. 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 aected 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 ammable and 
toxic gases but only hi-pressure air, nitrogen or refrigerant.
• 
Mineral scale on the surface of the heat exchanger will aect the heat exchanging eciency and increase 
the water resistance and lower the  refrigeration  capacity. Therefore, it should be cleared away through 
dilute acid. Note that contents of dierent water quality vary and should be treated with dierent type of 
acid by the qualied chemical company.
7.9 Removal of the Compressor
Please take the steps below when the compressor is required to be removed.
(1) Cut o 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.
(4) Unsolder the soldering spots of the suction and discharge lines.