Checking f o r Refrigerant System Leaks.

TM 5-4120-356-14

(2) Continually pass dry nitrogen through the tubing or connections being

s o l d e r e d or brazed to prevent the formation of harmful copper oxides.

(1) Turn the selector switch to the "OFF" position and disconnect the air

conditioner from the electrical power source.

(2) Refer to figure 4-5 and install pressure gages.

(3) If refrigerant system has been opened and refrigerant removed, pro-

ceed to step (5).

( 4 ) If refrigerant system has not been opened, check system static press-

If pressure on

u r e on the suction side and on the discharge side of the compressor.

b o t h t h e s u c t i o n s i d e a n d t h e d i s c h a r g e s i d e i s a t l e a s t 1 0 0 p s i g ( 7 . 0 k s / m c2 ) , pro-

o n b o t h t h e s u c t i o n s i d e a n d t h e d i s c h a r g e s i d e iS n o t

ceed to step (6). If pressure

a t l e a s t 1 0 0 p s i g ( 7 . 0 k s / c m,2 p r o c e e d w i t h s t e p ( 5 ) .

)

(5) Add vaporized refrigerant to both the suction side and the discharge

s i d e o f t h e c o m p r e s s o r t h r o u g h t h e s e r v i c e v a l v e s u n t i l the suction pressure and the

d i s c h a r g e pressure a r e at least 100 psig (7.0ks/mc2 ) .

(6) Using available leak detector, check areas of the refrigerant system

showing collected refrigerant oil and associated accumulated dust. Pinpoint and tag

e a c h leak found.

d. Repairing Refrigerant System Leaks.

( 1 ) R e f e r to paragraph 4-6 and release refrigerant from the system. Leave

s e r v i c e v a l v e s open.

( 2 ) If leak is to be brazed, proceed as follows:

( a ) Connect a source of v a p o r i z e d nitrogen to the service valve

closest to the leak.

(b) Release nitrogen into the system while brazing the leaking area.

( 3 ) If the leak is in a fitting, proceed as follows:

( a ) Remove the fitting and associated component from the system.

(b)

Clean

fitting.

CAUTION

U s e care in applying leak lock or high

v a c u u m grease so that when the fitting

is installed, none of the material gets

inside the refrigerant system.

4-8