Refrigerant Charge - Gree DC Inverter Multi VRF Service Manual

DC INVERTER MULTI VRF
Start the vacuum pump and turn on "L
b. Continue for 0.5~1.0 hour after the vacuum level reaches -0.1MPa (gauge pressure -1kgf/cm
Then, close the "VH" knob on high pressure end and "VL" knob on low pressure end to stop the
vacuum pump.
c. Remove the hose connected to vacuum pump and reconnect it to the refrigerant tank. Expel the
air in the hose. Open the "VL" knob on low pressure end to charge refrigerant to the system piping.
When the pressure reaches 0.0kgf/ cm
d.Remove the hose connected to refrigerant tank and reconnect it to vacuum pump. Start the
vacuum pump and open the "VH" knob on high pressure end. Pump for 30 minutes from high
pressure end and then open the "VL" knob to pump from low pressure end, until the vacuum level
reaches -0.1MPa
If the vacuum level reaches -0.1MPa (gauge pressure) or lower, the vacuuming process is then
ended. Stop the vacuum pump and place still for 1 hour. Then, check the vacuum level for any
change. n case of any change, it indicates that there is leakage. In this case, proceed to leakage
detection and repair.
e. Complete the vacuuming according to above procedures and then proceed to charging of
additional refrigerant

6.12 Refrigerant Charge

1 Calculation method for refrigerant charging
Refrigerant shall be charged according to calculated amount specified in engineering drawings.
Method for calculation of added refrigerant volume (based on liquid pipe)
Mass of refrigerant to be charged =∑ length of liquid pipe × refrigerant charge amount of every
meter of liquid pipe.
Medium
R22
R410a
Note: a. Standard pipe length is 15m. If refrigerant piping (L) is shorter than or equal to 15m, no
additional refrigerant is needed. If piping is longer than 15m (based on liquid pipe), more
refrigerant shall be added. The above table shows how much refrigerant shall be charged for
every one additional meter of piping.
b. Electronic balance shall be used for refrigerant charge
c. Thickness of pipe wall shall be 0.5 1.0mm and pressure-bearing capability shall be 3.0MPa
d. The longer the piping, the more refrigerating capacity and heating capacity shall be weakened.
2 Steps of refrigerant charge are as follows
a. The connecting hose of refrigerant cylinder shall be connected to the connector of the pressure
gauge. The valve V
H
the pressure gauge shall be connected to the refrigerant filling nozzle on the small valve of outdoor
unit.
Pressure gauge connector valve
Vacuum pump
" and "H
O
2
, close the "VL" knob on low pressure end.
-1kgf/cm
Amount of refrigerant charge for every meter of liquid pipe kg/m
Φ22.2 Φ19.05
0.41 0.29
0.35 0.25
shall be opened to discharge air in the hose. Then, the high pressure end of
Connector on gas side
Connector on liquid side
" knobs
I
2
Φ15.9 Φ12.7
0.187 0.12
0.17 0.11
INSTALLATION
Φ9.52 Φ6.35
0.06 0.03
0.054 0.022
2
).
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