Filter
Top Products
68
Fig. 7-4
(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:
Manifold valve
Pressure
gauge
Lo Hi
Vacuum pump
Outdoor unit
Close
Open
Liquid
tube
Gas
tube
Balance
tube
Close
Open
Close
Open
Required time for evacuation
when 30 gal/h vacuum pump is used
If tubing length is If tubing length is
less than 49 ft. longer than 49 ft.
45 min. or more 90 min. or more
07-007 W-2WAY_II_NA 1/23/07 6:09 PM Page 68