DC Inverter Side Discharge VRF Ⅱ for North America
124
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;
(3) Confirm that the gas valve and liquid valve for outdoor unit is at off status;
(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.
5.2.3 Notice for filling refrigerant
(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.
5.3 Airtightness test
5.3.1 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 ceiling decoration are all finished, it’s will be very difficult to
find out the leakage point. Thus, the airtightness test of the system must be finished before finishing
indoor decoration.
5.3.2 Operation procedure for the airtightness test
Before ex-factory, cut-off valve for gas pipe and liquid pipe of outdoor unit is turned off. Please
confirm that before operation.
Before testm please smear a little corresponding lubricant oil at Blanking plug. and pipe terminal,
and use two wrenches for fixing Blanking plug.
Do not allow to connect the pipeline of outdoor unit for test during airtightness test.
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:
Step 1: Increase pressure slowly to 0.5MPa, stop for 5min and then check the gas leakage. Big
To Next Page
Loading...
