TM 9-2320-280-34
14-27.4. AIR-CONDITIONING EVAPORATOR MAINTENANCE (R-134a) (Cont'd)
b. Disassembly
1.
Remove low-pressure switch (23) from outlet line (25).
2.
Remove two capscrews (8), nuts (11), clamps (9), and pressure lines (7) and (14) from brackets (12).
3.
Disconnect pressure lines (14) and (7) from sight glass (16) and remove sight glass (16), pressure
line (14), and two O-rings (15). Discard O-rings (15).
4.
Disconnect pressure line (7) from expansion valve (4). Remove and discard O-ring (6).
5.
Remove two capscrews (20), nuts (13), brackets (12), and spacers (10) from evaporator (2).
6.
Disconnect expansion valve line (5) from outlet line (25). Remove and discard O-ring (19).
7.
Remove nonmetallic seal (24) from evaporator outlet line (25) and expansion valve control tube (18).
Discard nonmetallic seal (24).
8.
Loosen clamp (17) securing control tube (18) to evaporator outlet line (25).
9.
Disconnect expansion valve (4) from evaporator inlet line (1) and remove expansion valve (4) and
O-ring (3). Discard O-ring (3).
10.
Remove two screws (22) and drain pan (21) from evaporator (2) .
11.
Inspect evaporator (2), expansion valve (4), pressure lines (7), (14), and (5), sight glass (16), and
low-pressure switch (23) for stripped threads, cracks, evidence of leakage, and damage. Replace
sight glass (16) and any other component if cracked, damaged, threads are stripped, or leakage is
evident.
c. Assembly
1.
Install drain pan (21) on evaporator (2) with two screws (22).
CAUTION
To prevent damage to control line tube during installation of
expansion valve, avoid excessive bending or kinking of
expansion valve control tube.
Avoid over tightening of expansion valve control tube retaining
clamp.
2.
Lubricate O-ring (3) with lubricating oil, install O-ring (3) and connect expansion valve (4) on
evaporator inlet line (1).
3.
Lubricate O-ring (19) with lubricating oil, install O-ring (19) and connect expansion valve line (5)
on outlet line (25).
4.
Install control tube (18) on outlet line (25) with clamp (17). Do not overtighten.
5.
Install low pressure switch (23) on outlet line (25).
6.
Insulate control tube (18), evaporator inlet line (1), and outlet line (25) with nonmetallic seal (24).
7.
Install two brackets (12) and spacers (10) on evaporator (2) with two capscrews (20) and nuts (13).
8.
Lubricate O-ring (6) with lubricating oil, install O-ring (6) and connect pressure line (7) on
expansion valve (4).
NOTE
Sight glass must face away from outlet line.
9.
Lubricate two O-rings (15) with lubricating oil, install two O-rings (15) and connect pressure
lines (7) and (14) on sight glass (16).
10.
Install two clamps (9) and pressure lines (7) and (14) on bracket (12) with two capscrews (8) and
nuts (11).
14-134.20
Change 2
