3.2 Evacuation①
Procedure:Remove the hose of the general purpose GM (or coolant
port) that was connected from the nitrogen cylinder, open the
nitrogen, shut the valve (or VR) of the removed hose, and
perform vacuum evacuation to fill the refrigerant. After
operating the powerful vacuum pump, open the valve of VC.
Vacuuming time: about 4 hours or more with a vacuum pump
with a capacity of 300 L / min (When using a vacuum pump
with a small capacity value, vacuuming is performed until the
degree of vacuum is 3 Torr or less as a guide)
3.3 Complete evacuation
Procedure : Specified time (about 4 hours or more) Shut each valve and stopper temporarily
after evacuation and stop the pump.
If vacuum evacuation on the low temperature side is carried out together,
disconnect from the refrigerant port.
(For high temperature side only, VR shut →)
-45-
Valve state
open
shut
○
VC
○
VG
○
VL
○
VH
○
VR