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(4) Do a leak test of all joints of the tubing (both indoor and outdoor) and
all service valves.
Bubbles 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 connector at the nitrogen
cylinder.
When the system pressure 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 operation time for evacuation varies with the tubing length and
capacity of the pump.
Evacuation is not necessary for the balance tube if only 1 outdoor unit
is installed.
NOTE
The vacuum condition should be less than –14.7 psig (-0.1MPa)
{–755 mmHg, 5 Torr}.
(2) When the desired vacuum is reached, close the “Lo” knob of the
manifold valve and turn off the vacuum pump.
Please confirm that the gauge pressure is under –14.7 psig (-0.1MPa)
{–755 mmHg, 5 Torr} after 4 to 5 minutes of vacuum pump operation.
Open
Open
Open
Close
Close
Outdoor unit
Close
Vacuum
gauge
Gas
tube
Liquid
tube
Balance
tube
Manifold valve
Vacuum pump
00_302411_EN.indd 38
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