Hitachi RAK-35NH5 - Servicing Work (Refrigerant recharging); Working steps

4. Servicing work (Rerfigerant recharging)
Working steps
Handle Hi
Compound
pressure gauge
Charge hose
Ball valve
Refrigerant
cylinder
Scale
Vacuum pump
adapter
Vacuum pump
Handle Lo
Ð0.1MPa
Pressure
gauge
Gauge manifold
Charge hose
Charge hose
Service port
Ball valve
Service valve (2-Way)
Service valve
(3-Way)
1. Connect the charge hose to outdoor unit.
2. Connect the vacuum pump adapter to the
vacuum pump. Connect the 1/2" conversion
adapter to the vacuum pump adapter.
Connect the charge hose to the conversion
adapter.
3. Connect the charge hose to the refrigerant
cylinder.
5. When the compound pressure gauge's
pointer has indicated -0.1MPa, place the
handle Lo in the fully closed position.
Then, service valve
&isclosed.
Run the vacuum pump in specified time.
4. Open the handle Lo .
Turn ON the power switch of the vacuum
pump & adapter.
Turn OFF the power switch of the vacuum
pump & adapter.
8. Calculation of charged refrigerant amount.
7. Air purge of gauge manifold.
Open the refrigerant cylinder's valve and
push the valve core at portion of gauge
manifold. Then the refrigerant is discharge in
a moment.
6. Remove the charge hose of vacuum pump
at portion .
9. Charging of refrigeration.
Open the handle Lo in a turn and charge
the designated amount.
13. Remove the charge hose & .
Remove the charge hose rom portion .
Remove the charge hose from portion .
10. Completion of charging.
11. Be closed the valve of charge hose .
12. Run the compressor at cooling operation.
14. Attach the caps.
15. Gas leakage check.
CAUTION
1. Be sure to use the vacuum pump, vacuum pump
adapter and gauge manifold to refer to their instruction
manuals beforehand.
2. Ascertain that the vacuum pump is filled with oil to the
level designated on the oil gauge.
3. After closed the ball valve of charge hose, it should be
disconnected at service port side and refrigerant cylinder
side at first.
Next, after discharging the remained gas in the charge
hose by opening the ball valve a little, disconnect it at
gauge manifold side. You can prevent from being
released the refrigerant suddenly by connecting the ball
valve to service port. And you can work with more
safety.
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