Fujitsu AS*7A Technical Manual page 153

(2) Outdoor unit side
Tighten the flare nut of the connection pipe at the
outdoor unit valve connector. The tightening
method is the same as that as at the indoor side.
Fig. 28
(Large pipe)
3-way valve
5. HEAT INSULATION ON THE PIPE JOINTS
(INDOOR SIDE ONLY)
Put coupler heat insulation on the joints (indoor side
only) (Fig. 29).
Fig.29
Indoor unit
No gap
Coupler heat
insulation (large)
Large pipe
Coupler heat insulation
5. AIR PURGE
1. AIR PURGE
(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.
Connection pipe
(Small pipe)
Flare nut
Pipe coupling
2-way valve
Coupler heat
insulation
(small)
}
Be sure to
overlap the
insulation
Small pipe
No gap
(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).
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 page 52.
4. GAS LEAKAGE INSPECTION
After connecting the piping, check the
joints for gas leakage with gas leak
detector.
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