b. EVACUATION PROCEDURE.
Start the vacuum pump.
Open the charging mantiold valves.
Open both unit service valves.
Run the vacuum pump until at least 29 inches of mercury is reached.
Inability to reach 29 inches of mercury may indicate a leak in the
refrigerant system or a problem with the vacuum pump.
Twenty-nine inches of mercury will not be reached at higher than sea
level elevations. Refer to Table 5-7 for corrective factors.
ELEVATION CORRECTION FOR VACUUM GAUGE READINGS
Continue running the pump for 1 hour, observing the vacuum pump gauge. If
the gauge needle moves back and forth, there is a refrigerant leak which must be located and
Close all manifold charging valves.
Close both unit service valves.
Stop vacuum pump.