1.6
Nitrogen charge before nitrogen blowdown
procedure
:
After 1.5 , VC, VG are shut, VR, VH, VL are opened and nitrogen is charged
(about 30 seconds) (however, the secondary pressure is 0.5-0.7 MPa)
note
:
In order to prevent air from entering the freezing circuit, fill with nitrogen.
1.7
Nitrogen blow
Procedure
:
Once all the valves are shut, reconnect as shown below and blow nitrogen for about
30 seconds into the circuit. (Nitrogen replacement: provided that the secondary
pressure is 0.5 to 0.7 MPa)
Caution! Since the refrigerant may burn with the flame of the welding machine, always carry out
the above procedure.
Note
:
Nitrogen blow is performed to completely release the refrigerant. The flow rate of nitrogen
may be small (to the extent that it feels a little with the skin).
Valve state
open
shut
VC
○
VG
○
VL
○
VH
○
VR
○
Valve state
open
shut
VC
○
VG
○
VL
○
VH
○
VR
○
outdoor
Charge hose
Nitrogen cylinder
Long hose
VR
VG
VL
VC
VH
Piercing tool
Low pressure side
service pipe
Refrigerant
port
Vacuum
port
High pressure port
Low pressure
port
Charge hose
Dedicated GM
Explosion-proof
vacuum pump
-41-
Summary of Contents for MDF-DU702VH
Page 8: ...Dimension MDF DU502VH 5 ...
Page 9: ...MDF DU702VH 6 ...
Page 17: ...Wiring Diagram 14 ...
Page 18: ...main Circuit Diagram 15 ...
Page 19: ...power 16 ...
Page 20: ...USB 17 ...
Page 73: ...WIRING YG Y Y GR B G W W W Y G R BL Y W R R BL R OR B BL R OR B Y W Y G Y G R BL 70 ...