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).
Confirm 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 sides of Gas and Liquid).
7. Remove the charging hose from the service port.
8. Securely tighten the caps on the packed valves.
FILE NO. SVM-13001
Incused line
10-4-4. Evacuating
After the piping has been connected to the indoor unit,
you can perform the air purge together at once.
<Shaping pipes>
1. How to shape the pipes. Shape the pipes along
the incused line on the outdoor unit.
Fig. 10-4-8
2. How to fit position of the pipes. Put the edges of
the pipes to the place with a distance of 85 mm
from the incused line.
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 vacuum pump manual.
Packed valve at liquid side
Pressure gauge
Manifold valve
Packed valve at gas side
Vacuum pump
adapter for
counter-flow
prevention
−
101 kPa (
−
76 cmHg)
Handle Lo
Compound pressure gauge
Charge hose
Connecting pipe
Vacuum
pump
Charge hose
Handle Hi
(Keep full closed)
Service port
(Valve core (Setting pin))
(For R410A only)
(For R410A only)
(For R410A only)
<Use 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 the vacuum pump enters
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 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.
Fig. 10-4-8
(5) Be sure to fully open the packed valves
before operation.
•
KEEP IMPORTANT 5 POINTS FOR PIPING WORK
(1) Take away dust and moisture (Inside of the
connecting pipes.)
(2) Tighten connection (between pipes and unit)
(3)
Evacuate the air in the connecting pipes using
VACUUM PUMP.
(4)
Check gas leak (connected points)
CAUTION
– 65 –