Vacuum And Refrigerant Charge - Gree GMV-WQ72WM/A-F Owner's Manual

Water-cooled Heat Recovery DC Inverter VRF
Polyethylene foam can sustain 120℃(248℉) or above and foaming polyethylene can
sustain 100℃(212℉) or above.
3) Joints at indoor and outdoor units should be wrapped with thermal insulator and no
clearance between pipe and wall. Show as Fig.4.3.6.
4) Manifold attached foam cannot be taken as insulating material.
5) When wrapping the tape, the later circle should cover half of the former one. Don't wrap
the tape too tight, otherwise the insulation degrades.
6) After wrapping the pipe, adopt sealing material to completely fill the hole to prevent wind
and rain entering the room.
4.3.4 Support and protection for pipeline
(1) Support should be made for hanging connection pipe. Distance between each support
cannot be over 1m (39-3/8in.).
(2) Protection towards accidental damage should be made for outdoor pipeline. If the pipe
exceeds 1m (39-3/8in.), a pin board should be adopted for protection.

4.4 Vacuum and Refrigerant Charge

4.4.1 Vacuum
(1) Before vacuum, make sure that outdoor liquid pipe/low pressure gas pipe/high pressure gas
pipe valves are all closed. Apply vacuum pumps to pump out air from IDUs and connection
pipe through the fluorine injection nozzles at the outdoor liquid pipe/low pressure gas
pipe/high pressure gas pipe valves of ODU. Connection graph is shown as Fig.4.4.1 and
Fig.4.4.2.
(2) Vacuum connection method for more than 2 ODUs is the same.
Fig.4.3.6
High pressure
Low pressure
Gas Pipe
Liquid Pipe Gas Pipe
Fig.4.4.1
16
Low pressure
Check Valve