76 S417954476 S4179544
11
11
1
AS
22
22
2
S
33
33
3
X
00
00
0
C
To avoid nitrogen entering
the refrigerant system in a
liquid state, the top of the
cylinder must be higher than
the bottom when you pres-
surize the system.
Usually, the cylinder is used
in a vertical standing posi-
tion. (Refer to the previous
page.)
(4) Do a leak test of all joints of the tubing (both
indoor and outdoor) and both wide and narrow
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. The
following table shows the amount of time for
evacuation:
The required time in the above table is calculated
based on the assumption that the ideal (or target)
vacuum condition is around 10 mmHg abs.
(2) When the desired vacuum is reached, close the
“Lo” knob of the manifold valve and turn off the
vacuum pump.
Charging additional refrigerant
● Charging additional refrigerant (calculated from the
narrow tube length as shown in Section 1-8
“Additional Refrigerant Charge”) using the narrow
tube service valve.
● Use a balance to measure the refrigerant
accurately.
CAUTION
If tubing length is
less than 15 m
45 minutes or more
If tubing length is
longer than 15 m
90 minutes or more
Required time for evacuation
when 30 gal/h vacuum pump is used
NOTE
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