Panasonic R410A: 5/16 Installation Instructions Manual page 33

(4) Do a leak test of all joints of the tubing (both indoor and
outdoor) and both gas and liquid service valves. Bub-
bles indicate a leak. Wipe off the soap with a clean cloth
after a leak test.
(5) After the system is found to be free of leaks, relieve the
nitrogen pressure by loosening the charge hose con-
nector at the nitrogen cylinder. When the system pres-
sure is reduced to normal, disconnect the hose from the
cylinder.
Evacuation
(1) Attach the charge hose end described in the preceding
steps to the vacuum pump to evacuate the tubing and
indoor unit. Confirm that the "Lo" knob of the manifold
valve is open. Then, run the vacuum pump. The opera-
tion time for evacuation varies with the tubing length and
capacity of the pump. The following table shows the
amount of time for evacuation:
Required time for evacuation
when 30 gal/h vacuum pump is used
If tubing length is
less than 49 ft.
45 min. or more
NOTE
The required time in the above table is calculated based on
the assumption that the ideal (or target) vacuum condition is
less than –14.7 psig (–755 mmHg, 5 Torr).
If tubing length is
longer than 49 ft.
90 min. or more
33
Manifold valve
Pressure
Lo Hi
gauge
Vacuum pump
Open
Gas
tube
Open
Liquid
tube
Open
Balance
tube
Fig. 6-4
Close
Outdoor unit
Close
Close