Gree R410A Manual Download Page 85

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for North America

NOTICE!

Liquid pipe that is within 20m(65-5/8 feet) doesn’t need to be added refrigerant.

Therefore, the minimum quantity of additional refrigerant = (23-20)×0.054+11×0.022=

0.404kg(14oz).
5.3.2 Operation procedure for adding refrigerant

(1) Put the charging tank on the weightometer, record the reading and then calculate the

data after charging refrigerant;

(2) Use charging conduct pipe to connect the double-ended manometer with governing valve

and liquid-charging tank to the detection head of gas valve and liquid valve. Before

connection, please release some refrigerant and then drain out the air inside the charging

conduct pipe.

(4) When the unit hasn’t been turned on, open the governing valve for the liquid-charging

tank and then charge refrigerant from gas pipe and liquid pipe at the same time.

(5) Obeserve the data weightometer, close the valve after it is reached to requirement and

then close the valve for liquid-charging tank;

(6) If the refrigerant can’t be added completely, add it when turning on the unit. Charge

refrigerant from the detection joint of cooling gas pipe or detection joint of gas vavle.

(1) Calculate the section and length of cooling liquid pipe preciously for the precision

refrigerant-charing volume.

(2)  Measure the additional refrigerant volume preciously;
(3)  Invert to charge the R410A for ensuting the liquid-charging;
(4)  When the temperature is low, heat the liquid-storage tank with hot water or hot

wind for helping refrigerant-charging. However, prohibit use flame to heat the

liquid-storage tank directly. Otherwise, it may cuase personal injury or property

damage due to explosion.

Confirm that the gas valve and liquid for outdoor unit is at of status.

(3)

5.3.3 Notice for filling refrigerant

5.4 Airtightness test

5.4.1 Importance of airtightness test
The airtightness of VRF system is the leak tightness of the pipeline for refrigerant,

which the guarantee for safe and reliable operation. The leakage of refrigerant may

affect the operation of air conditioner seriously, or even damage compressor and then

lead to breakdown of system. Therefore, it needs to perform the airtightness test.

If the there’s gas leakage after the system is installed completely, because the indoor

celling decoration are all finished, it is will be very difficult to find out the leakage point.

Thus, the airtightness test of the system must be finished before finishing indoor

decoration.

5.4.2 Operation procedure for the airtightness test

(2) Before test please smear a little corresponding lubricant oil at Blanking plug and

pipe terminal, and use two wrenches for fixing blanking plug.
(3) Do not allow to connect the pipeline of outdoor unit for test during airtightness test.

(4) The system test pressure for R410A is 4.15MPa (3.0MPa for R22 refrigerant

system). Nitrogen must be used as the medium for the airtightness test and the nitrogen

should be dry. Increase pressure slowly for three steps:

(1) Before ex-factory,cut-off valve for gas pipe and liquid pipe of outdoor unit is

turned off, Please confirm that before operation;

Photovoltaic Direct-driven VRF