AIR DEMAND REGULATOR TROUBLESHOOTING INSTRUCTIONS

TB 5-4220-200-12-1

Table 4-3. TROUBLESHOOTING - UNIT (CONT)

A. AIR DEMAND REGULATOR TROUBLESHOOTING INSTRUCTIONS (CONT)

ITEM

NO.

MALFUNCTION

PROBABLE CAUSE

CORRECTIVE ACTION

Air leakage (submerge a. Second stage regulator diaphragm

a. Check and replace if neces-

pressure regulator

(fig. 4-2) (6) damaged. or improper

sary. (Section V, para 4-14b).

in water to locate

seal between the box top (fig. 4-2)

(5) and the box bottom (fig. 4-2) (11).

source of leak).

b. Tighten rim clamp screw

b. Loose rim clamp (fig. 4-2) (6).

(7), (Section V, para 4-14b).

C. Loose inlet fitting (fig. 4-2) (12).

c. Tighten inlet fitting (12),

(Section V, para 4-14b).

d. inlet fitting O-Ring (fig. 4-2) (13)

d. Clean or replace (Section III,

dirty, damaged, or worn.

para 4-7).

e. First stage regulator spring re-

e. Tighten spring retainer

tainer (fig. 4-1) (26).

(26), (Section V, para 4-13b).

First stage regulator plug screws

f. Tighten plug screw.

(fig. 4-1) (17) and 4-1) (18) loose.

g. First stage regulator plug screw

g. Clean or replace (Section III,

O-Rings (fig. 4-1) (16) and (19) dirty

para 4-7).

or damaged.

h. Hose connectors (fig. 4-2) (25)

h. Tighten hose connections

and (27) loose or damaged.

or replace hose (26).

Clean or replace O-Ring

Hose O-Rings (fig. 4-2) (24) and

(Section III. para 4-7).

(28) dirty, damaged, or worn.

Hose (fig. 4-2) (26) cracked or

j. Replace hose (26).

worn.

Water Leakage.

a. Exhaust valve (fig 4-2) (10) dirty,

a. Clean of replace (Section III,

damaged, or worn.

para 4-7), or Section V, para

4-14b).

b. Check points listed under "air

leakage," A and B item No. Six.

C. Mouthpiece torn or Loose band

(Mouthpiece).

4-5