Toshiba RAS-B05BKVG-E Service Manual page 65

AIR PURGE
Ev acuate the air in the connecting pipes and in the
indoor unit using a v acuum pump. Do not use the
refriger ant in the outdoor unit. For details, see the
manual of the vacuum pump.
<Using a vacuum pump>
Be sure to use a vacuum pump with counter-flow
prevention function so that inside oil of the pump does
not flow backward into pipes of the air conditioner
when the pump stops. (If oil inside of the vacuum
pump enters into the air conditioner, which use R32,
refrigeration cycle trouble may result.)
1. Connect the charge hose from the manif
the service port of the gas side packed valve.
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 confirm that the compound
pressure gauge reading is -101 kP a (76 cmHg).
5. Close the low pressure side valve handle of gauge
manifold.
6. Open fully the valve stem of the packed valves
(both side of Gas and Liquid).
7. Remove the charging hose from the service port.
8. Securely tighten the caps on the packed valves.
Compound pressure gauge
–101 kPa (-76 cmHg)
Handle Lo
Charge hose (For R32 only)
Connecting pipe
Packed valve at gas side
Service port (Valve core (Setting pin))
Packed valve at liquid side
Fig. 10-4-7
old valv e to
Pressure gauge
Manifold valve
Handle Hi (Keep full closed)
Charge hose (For R32 only)
Vacuum pump adapter for
counter-flow prevention
(For R32 only)
Vacuum
pump
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CAUTION
•
KEEP IMPORTANT 6 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 flared
joints are not allowed indoors. When
mechanical connectors are reused indoors,
sealing parts shall be renewed. When flared
joints are reused indoors, the fl are part shall be
refabricated.
<Packed valve handling precautions>
• Open the valve stem all the way out, but do not try
to open it beyond the stopper.
Pipe size of Packed Valve
12.70 mm and smallers
15.88 mm
• Securely tighten the valve cap with torque in the
following table
Cap Cap Size (H)
H17 - H19
Valve Rod
Cap
H22 - H30
H14
Service
Port Cap
H17
Hexagon wrench
is required.
Service Port Cap
Valve Rod Cap
Fig. 10-4-8
FILE NO. SVM-18006
Size of Hexagon wrench
A = 4 mm
A = 5 mm
Torque
14~18 N.m
(1.4 to 1.8 kgf·m)
33~42 N.m
(3.3 to 4.2 kgf·m)
8~12 N.m
(0.8 to 1.2 kgf·m)
14~18 N.m
(1.4 to 1.8 kgf·m)
A
H