6. VACUUM PROCESS
1. VACUUM
(1) Remove the cap, and connect the gauge manifold
and the vacuum pump to the charging valve by the
service hoses.
(2) Vacuum the indoor unit and the connecting pipes until
the pressure in them lowers to below 1.5 mmHg.
(3) Disconnect the service hoses and fit the cap to the
charging valve (Tightening torque : 70 to 90 kgf
cm).
•
(4) Remove the blank caps, and fully open the spindles
of the 2-way and 3-way valves with a hexagon
wrench (Torque : 2-way valve : 70 to 90 kgf
cm,
•
3-way valve : 100 to 120 kgf
cm).
•
(5) Tighten the blank caps of the 2-way valve and 3-way
valve to the specified torque (200 to 250 kgf
cm).
•
Fig. 31
Refrigerant pipe
Gauge
manifold
3-way valve
Outdoor
unit
Service hose
Blank cap
Vacuum
with valve
pump
core
Charging
valve
Cap
Service hose
2. ADDITIONAL CHARGE
Refrigerant suitable for a piping length of 5 m is
charged in the outdoor unit at the factory.
When the piping is longer than 5 m, additional charg-
ing is necessary.
For the additional amount, see the table below.
Table 5
25 ft
33 ft
49 ft
66 ft
Pipe length
(7.5 m)
(10 m)
(15 m)
(20 m)
Additional
2.1 oz
4.2 oz
6.3 oz
None
refrigerant
(60 g)
(120 g)
(180 g)
Between 5 m and 20 m, when using a connection pipe
other than that shown in the table, charge additional
refrigerant with 0.42 oz (12g) / 3.3 ft (1 m) as the criteria.
(1) Always pump down the piping
before use.
(2) Add refrigerant from the charging
valve after the completion of the
work.