Methods For Vacuum Pumping And Charging Refrigerant Of System - Gree GMV-VQ680WM/C-X Service Manual

Gree
3 Methods for Vacuum Pumping and Charging Refrigerant
of System
3.1 System vacuum pumping method
Vacuum pumping method of heat recovery multi VRF unit include vacuum pumping operation
for complete system and vacuum pumping operation for the system without outdoor unit.
3.1.1 Selection requirements for vacuum pumps
1) Can't vacuumize different refrigerant systems with the same vacuum pump.
2) The ultimate vacuum of the vacuum pump should be -0.1MPa.
3) The air displacement of the vacuum pump should be above 4L/S.
4) The accuracy of the vacuum pump should be above 0.02mmHg.
5) The system vacuum pump must have a check valve.
3.1.2 Operating procedures for vacuum pumping
3.1.2.1 Vacuum pumping operation for complete system
For a complete system including outdoor unit, mode exchange box, and indoor unit, perform
vacuuming as follows:
1）Before vacuum pumping, if there is no need to conduct vacuum pumping for the outdoor
unit, please confirm that the high-pressure gas pipe, low-pressure gas pipe, and cut-off valve are
in close status; if the outdoor unit needs to conduct vacuum pumping, please confirm that the
high-pressure gas pipe, low-pressure gas pipe, and cut-off valve are in open status.
2）Ensure that the pipeline connection and communication connection among outdoor unit,
mode exchange box and indoor unit are well connected; the outdoor unit, mode exchange box and
indoor unit should all be energized and maintain off status.
3）Control the outdoor unit to enter the vacuum pumping mode (A8) through mainboard
function buttons of the outdoor unit, debugging software or s multi-functional debugger, at this time
the solenoid valve and electronic expansion valve in the system will automatically open.
4）Connect the regulating valve and the vacuum pump to the detection joints of the
high-pressure gas pipe valve, low-pressure gas pipe valve and liquid pipe valve with charging
pipe.
GMV6 HR DC Inverter VRF Units Service Manual
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