(14) Purge the system above 15 psig with nitrogen per steps 2 through 7, except step 4.
(15) Pull a second vacuum down to 28 to 30 inches of vacuum per steps 10 through 12.
Figure 3-6. R22 Refrigerant System Servicing (Sheet 6 of 10)
(16) Close system to the compressor (17) by turning compressor service discharge valve (14) and
compressor service suction valve (15) clockwise to their closed (full front seated) position.
(17) Continue to pull vacuum down to 28 to 30 inches of vacuum.
(18) Close system. Turn manifold gage set valves (3 and 4) clockwise to their closed (full front seated)
position. The system should stay below 26 inches of vacuum after 15 minutes.
(19) Turn compressor service discharge valve (14) and compressor service suction valve (15) to their
open (full back seated) position. If the system does not stay below 26 inches of vacuum, repeat
steps 4 through 17.
(21) Check the filter/drier sight glass (19). If other than blue in color, repeat steps 15 through 20.
If air conditioning system required the replacement of a major component, compressor oil
may have to be added to system to compensate for loss (refer to para 3.9.1.c.).
(2) Install tee (12) to manifold gage sets center hoses (11).
Install center hose (13) to R22 refrigerant container and tee (12).