TM 5-4220-227-14
4-30. Water Valves (3/4 in.) (Cont).
WARNING
Leave 1 1/2 threads exposed on fitting when applying teflon tape. This will ensure that no teflon tape will
hang down inside the air system Teflon tape should be wrapped in such a manner that when the fitting is
tightened the tape will not loosen. Failure to wrap teflon tape correctly may result in contamination or
blockage of the air system and subsequent possible injury or death to the diver.
(6)
Apply teflon tape to all pipe threads.
(7)
Install valve (1) on nipple (5).
(8)
Install elbow (4) on valve (1).
(9)
Install line (3) and tighten fitting nut (2).
(10)
Open valve (1) and start up heater/chiller module to pressure check the system.
b. Repair. (figure 4-13)
(1)
Remove heater/chiller fluid valve, see para. a. above.
(2)
Remove nut (1), stem spring (2), plate (3), stop plate (4), handle (5), and spring (6).
(3)
Remove nut (7), two stem springs (8), gland (9), packing support (10), top packing (11), and bottom packing (12).
(4)
Remove eight nuts (13), four stud bolts (14), and two flanges (15) from body (16).
(5)
Remove two preformed packings (17), seat springs (18), seats (19), support rings (20) and ball (21) from body
(16).
(6)
Remove stem (22), and two stem bearings (23) from body (16).
(7)
Clean all components using nonionic detergent cleaner and rinse with clean distilled water.
(8)
Inspect all items and replace all items that are bent, cracked, worn, or otherwise damaged.
(9)
Install two stem bearings (23) on stem (22) and install stem into body (16).
(10)
Install ball (21), two support rings (20), seats (19), seat springs (18), and preformed packings (17) in body (16).
(11)
Install two flanges (15) on body (16) and secure with four stud bolts (14) and eight nuts (13).
(12)
Install bottom packing (12), top packing (11), packing support (10), glands (9), two stem springs (8), and nut (7).
(13)
Install spring (6), handle (5), stop plate (4), plate (3), stem spring (2), and nut (1).
(14)
Install heater/chiller fluid valve, see para. a above.
4-36
