–
59
–
FILE NO. SVM-12050
Fig. 10-4-5
(Unit : N·m)
Flare at indoor unit side
Flare at outdoor unit side
Mark line
Outer dia.
Tightening torque
of copper pipe
∅
6.35 16 to 18 (1.6 to 1.8 kgf·m)
∅
9.52 30 to 42 (3.0 to 4.2 kgf·m)
∅
12.70 50 to 62 (5.0 to 6.2 kgf·m)
.
10-4-3. 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.
1. Connect the charge hose from the manifold valve to the
service port of the gas side packed valve at gas sige.
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 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.
Fig. 10-4-7
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))
CAUTION
KEEP IMPORTANT 5 POINTS FOR PIPING WORK
(1) Take away dust and moisture (Inside of the
connecting pipes.)
(2) Tight connection (between pipes and unit)
(3)
Evacuate the air in the connecting pipes using
VACUUM PUMP.
(4)
Check gas leak (connected points)
(5) Be save to fully open the packed valves
before operation.
CAUTION
Do not apply excess torque.
Otherwise, the nut may crack depending on the
conditions.
<
Shaping pipes>
1. How to shape the pipes. Shape the pipes along
the incused line on the outdoor unit.
Fig. 10-4-6
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.
(If oil inside of the vacuum pump enters the air conditioner,
which use R410A, refrigeration cycle trouble may result.)
