Figure 6-3. Solenoid Valve, Exploded View

TM 5-4120-352-14

6-7.

Solenoid Valve

R e p a i r i n g Refrigerant Leaks

6-4.

a. General. Replaceable parts are the coil bon-

a. Locate leak (para 4-52).

net assembly, diaphragm and the preformed pack-

b. Discharge system (figure 6-1), repair leak,

ing. See figure 6-3.

and recharge system (para 6-3).

NOTE

If soldering is necessary on any part of the system, a

constant purge of dry nitrogen must be fed through

the system being soldered to prevent scale for-

mation within the system

6-5.

Decontamination

a. General. The compressor is a hermetically

sealed unit and cannot be repaired. An inoperative

compressor is usually due to a mechanical failure or

motor burnout. If the compressor is mechanically fro-

zen or sustains a motor burnout, it must be re-

placed. A compressor failure generates high tem-

perature causing a breakdown of oil, refrigerant

and motor insulation, with the resulting formation

of acid, moisture, sludge. The products are ex-

tremely corrosive and must be flushed from the sys-

tem or repeated burnouts will occur.

b. Procedure.

(1) Discharge system and purge with nitrogen

(figure 6-1).

(2) Remove defective motor-compressor (para

5-17).

(3) Remove dehydrator (para 5-24).

(4) With compressor out of system, purge all

lines with dry nitrogen.

(5) Install a new compressor (para 5-17) con-

taining a full and proper oil charge.

(6) Install new dehydrator (para 5-24). In step

10 this dehydrator will again be replaced.

(7) Triple evacuate system and charge with

refrigerant R22.

(8) Start air conditioner (para 2-10) and oper-

TS 4120-352-14/6-3

ate unit for 24 hours.

(9) Discharge system and purge with nitrogen

(para 6-3).

1. Coil

(10) Install new dehydrator (para 5-24).

2. Diaphragm

(11) Evacuate system and recharge with re-

3. Preformed packing

4. Bonnet assembly

frigerant (para 6-3).

(12) Operate air conditioner.

6-6.

Evaporator and Condenser Coils

a. Inspection. Inspect coils for damaged tubing

and bent fins. Inspect threaded holes for damaged

or stripped threads.

b. Repair. Repair any leaks. Straighten bent

fins. Repair or replace damaged tubing if possible.

Figure 6-3. Solenoid Valve, Exploded View

Replace coil if repair is not practical.

6-6