TM 9-2320-387-24-2
25-46
Change 1
25-15. A/C SYSTEM SERVICING (Cont’d)
f. Charging System
NOTE
If A/C system requires replacement of a major component or has
been flushed, refrigerant oil must be added to system to
compensate loss (refer to task g.).
1.
Evacuate A/C system (refer to task e.).
2.
Connect refrigerant R-134a source to center hose (5) of manifold gauge set (3).
3.
Open refrigerant R-134a source to allow refrigerant to flow into center hose (5).
4.
Purge center hose (5), low-pressure hose (6), and high-pressure hose (4) as follows:
a. Slightly loosen center hose (5) at center port (7) of manifold gauge set (3) until refrigerant
escapes, then tighten hose (5).
b. Open high-pressure gauge valve (2) and low-pressure gauge valve (1) to allow refrigerant to flow
into high-pressure hose (4) and low-pressure hose (6).
c. Purge high-pressure hose (4) and low-pressure hose (6) at service ports on compressor.
d. Turn high-pressure gauge valve (2) and low-pressure gauge valve (1) clockwise to OFF position.
5.
Connect STE/ICE-R (para. 2-47) to obtain engine rpm reading.
WARNING
Ensure high-pressure gauge valve is in closed position on
manifold gauge set during charging. Failure to do so will cause
compressor to build pressure in refrigerant container, causing
injury to personnel or damage to equipment.
6.
Start engine and set engine speed to 1,500 rpm with hand throttle (TM 9-2320-387-10).
7.
Turn on A/C system (TM 9-2320-387-10) and set blower fans on high speed.
NOTE
Keep refrigerant container upright at all times so refrigerant
enters system as a gas.
8.
Open low-pressure gauge valve (1) on manifold gauge set (3) until system is fully charged with 3 lbs
4 oz of R-134a refrigerant (refer to table 14-2).
9.
Close low-pressure gauge valve (1) on manifold gauge set (3).
10.
Return hand throttle to normal idle (TM 9-2320-387-10).
11.
Stop engine (TM 9-2320-387-10).
12.
Remove refrigerant R-134a source from center hose (5) of manifold gauge set (3).
13.
If no refrigerant oil is needed, disconnect manifold gauge hoses (4) and (6) from A/C system service
ports (9) and (10). Install caps (8) on service ports (9) and (10). If refrigerant oil is needed, perform
task g.
