−
41
−
<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 stem cap with torque in
the following table:
Fig. 8-5-8
4 m
m
Hexagonal wrench
is required.
Gas side
50 to 62 N·m
(
∅
12.70 mm)
(5.0 to 6.2 kgf·m)
Liquid side
16 to 18 N·m
(
∅
6.35 mm)
(1.6 to 1.8 kgf·m)
Service port
9 to 10 N·m
(0.9 to 1.0 kgf·m)
8-5-3. 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.
<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 R410A,
refrigeration cycle trouble may result.)
1. Connect the charge hose from the manifold valve to
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 kPa (
−
76 cmHg).
5. Close the low pressure side valve handle of gauge
manifold.
6. Open fully the valve stem of the packed valves
(both sides of Gas and Liquid).
7. Remove the charging hose from the service port.
8. Securely tighten the caps on the packed valves.
Fig. 8-5-7
Packed valve at liquid side
Pressure gauge
Manifold valve
Packed valve at gas side
Vacuum pump
adapter for
counter-flow
prevention
(For R410A only)
-101kPa (-76cmHg)
Handle Lo
Compound pressure gauge
Charge hose
(For R410A only)
Connecting pipe
Vacuum
pump
Charge hose
(For R410A only)
Handle Hi
(Keep full closed)
Service port
(Valve core (Setting pin))
FILE NO. SVM-06027
