ARMY TM 9-4120-380-14
AIR FORCE TO 35E9-136-21
5.11. PURGING REFRIGERANT SYSTEM. Continued
a. If system was pumped down, connect manifold red hose to expansion service valve (V3) in air conditioner
b. Connect yellow 1/4-inch (0.64 cm) charging hose (fig. S-S) from charge port to nitrogen regulator and dry
Loosen low pressure hose (blue) at compound gauge port of service manifold.
d Open PGV on service manifold, then open expansion service valve (V3)
e. Open charging valve (CV) on service manifold
Open the nitrogen cylinder valve and adjust the regulator so that less than 1-2 cfm (0.028-0 057 m3/minute) of
nitrogen flow rate is established
g. Check to insure that nitrogen is flowing from loosened hose at compound gauge port of service manifold
h. Allow nitrogen to sweep through the system for a minimum of 5 minutes before brazing or debrazing operations
(paragraph 5.12) are started. Continue sweep during the operation and for
5 minutes after completion.
i. Close nitrogen cylinder valve, service manifold valves, high and low pressure service valves on the compressor,
and expansion service valve (V3).
Disconnect hose from nitrogen regulator and return it to hose rack
Assuming that all repairs are completed, go to Leak Testing Refrigerant System (paragraph 5.13).
Figure 5-5. Purging Refrigerant System