Lennox Elite XC13 Installation Instructions Manual page 17

NOTE − Remove cores from service valves if not already done.
OUTDOOR UNIT
NITROGEN
VACUUM PUMP
Figure 29. Typical Evacuation Manifold and Micron Gauges Connections
5. Shut off the dry nitrogen cylinder and remove the
manifold gauge hose from the cylinder. Open the
manifold gauge valves to release dry nitrogen from the
line set and indoor unit.
6. Reconnect the manifold gauge to vacuum pump, turn
pump on, and continue to evacuate line set and indoor
unit until the absolute pressure does not rise above
500 microns (29.9 inches of mercury) within a
20−minute period after shutting off vacuum pump and
closing the manifold gauge valves.
7. When the absolute pressure requirement above has
been met, disconnect the manifold hose from the
vacuum pump and connect it to an upright cylinder of
A34000 1/4 SAE
TEE WITH
MICRON GAUGE
A
SWIVEL
COUPLER
C
B
D
A Connect low side of manifold gauge set with 1/4 SAE in−line tee to suction line
service valve
B Connect high side of manifold gauge set to liquid line service valve
HFC−410A
C Connect micron gauge available connector on the 1/4 SAE in−line tee.
D Connect the vacuum pump (with vacuum gauge) to the center port of the
manifold gauge set. The center port line will be used later for both the
HFC−410A and nitrogen containers.
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50
TO SUCTION
SERVICE VALVE
HFC−410A refrigerant. Open the manifold gauge valve
pressure line set to break vacuum with 2 to 5 psi.
8. Perform the following:
A Close manifold gauge valves
B Shut off HFC−410A cylinder
C Reinstall service
manifold hose from service valve. Quickly install
cores with core tool while maintaining a positive
system pressure.
D Replace the stem caps and secure finger tight,
then tighten an additional one−sixth (1/6) of a turn
as illustrated in figure 1.
MANIFOLD
GAUGE SET
TO LIQUID
LINE SERVICE
VALVE
RECOMMEND MINIMUM
3/8" HOSE
valve cores by removing
XC13 SERIES