Toshiba RAS-18J2AVSG-E1 Installation Manual Download Page 13

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CAUTION

Should be check the compressor operating condition while pumping
down process. It must not any abnormal sound, more vibration.
It is abnormal condition appears and must turn off the Air Conditioner
immediately.

Pump down process

1. Turn off the Air Conditioner system.
2. Connect the charge hose from the manifold valve to the service port of

the packed valve at gas side.

3. Turn on the Air Conditioner system in cooling operation more than

10 minutes.

4. Check the operating pressure of the system should be normal value.

(Ref. with product specifi cation)

5. Release the valve rod cap of both service valves.
6. Use the Hexagon wrench to turning the valve rod of Liquid side fully

close. (*Make sure no entering air into the system)

7. Continue operate Air Conditioner system until and the gauge of manifold

dropped into the range of 0.5 - 0 kgf/cm²

8. Use the Hexagon wrench to turning the valve rod of Gas side fully close.

And turn off the Air Conditioner system immediately thereafter.

9. Remove the gauge manifold from the service port of the packed valve.
10. Securely tighten the valve rod cap to the both service valves.

Evacuating

After the piping has been connected to the indoor unit, you can perform the
air purge together at once.

AIR PURGE

Evacuate the air in the connecting pipes and in the indoor unit using a
vacuum pump. Do not use the refrigerant in the outdoor unit. For details,
see the manual of the vacuum pump.

Be sure to use a vacuum pump with counter-fl ow prevention function so that
inside oil of the pump does not fl ow backward into pipes of the air condi-
tioner when the pump stops.
(If oil inside of the vacuum pump enters the air conditioner, which use
R32 or R410A, refrigeration cycle trouble may result.)
1. Connect the charge hose from the manifold valve to the service port of the

packed valve at gas side.

2.  Connect the charge hose to the port of the vacuum pump.
3.  Open fully the low pressure side handle of the gauge manifold valve.
4.  Operate the vacuum pump to start evacuating. Perform evacuating for

about 15 minutes if the piping length is 20 meters. (15 minutes for 20
meters) (assuming a pump capacity of 27 liters per minute) Then confi rm that
the compound pressure gauge reading is –101 kPa (–76 cmHg).

5.  Close the low pressure side valve handle of the gauge manifold valve.
6.  Open fully the valve stem of the packed valves (both gas and liquid sides).
7.  Remove the charging hose from the service port.
8.  Securely tighten the caps on the packed valves.

Using a vacuum pump

Packed valve at liquid side

Service port (Valve core (Setting pin))

Packed valve at gas side

Vacuum

pump

Vacuum pump adapter for
counter-fl ow prevention

Charge hose

Handle High
(Keep full closed)

Manifold valve

Pressure gauge

Compound pressure gauge

Handle Low

Charge hose

Connecting pipe

–101 kPa

(–76 cmHg)

CAUTION

KEEP IMPORTANT 7 POINTS FOR PIPING WORK.

  (1)  Take away dust and moisture (inside of the connecting pipes).
  (2)  Tighten the connections (between pipes and unit).
  (3)  Evacuate the air in the connecting pipes using a VACUUM PUMP.
  (4)  Check gas leak (connected points).
  (5)  Be sure to fully open the packed valves before operation.
  (6)  Reusable mechanical connectors and fared joints are not allowed

indoors. When mechanical connectors are reused indoors, sealing
parts shall be renewed. When fared joints are reused indoors, the
fare part shall be refabricated.

(7) Don’t operate air conditioner in case no refrigerant in the system.

Packed valve handling precautions

Open the valve stem all the way out, but do not try to open it beyond the

stopper.

Securely tighten the valve cap with torque in the following table:

Pipe size of Packed Valve

Size of Hexagon wrench

12.70 mm and smallers

A = 4 mm