Aqua Lung EA-4500 LW Technical Manual page 20

20
TABLE 1: TROUBLESHOOTING GUIDE FIRST STAGE
SYMPTOM
System will not remain depressurized after
handwheel is closed and second stage is
purged.
High or Unstable MP "Creep"
Low MP
External Air Leak
Restricted Air Flow or High Inhalation
Resistance
POSSIBLE CAUSE
1. The seat disc & retainer (16) is worn or
damaged.
2. The seat disc & retainer crown in HP module
body (13) is worn or damaged.
1. HP valve (9) is dirty, worn or damaged.
2. HP valve crown in LP module body (8) is
worn or damaged.
3. The seat disc & retainer crown in HP module
body (13) is worn or damaged.
4. The o-ring (11) inside HP balance chamber
is worn or damaged.
5. The HP balance chamber in HP module
body (13) is worn or damaged.
1. The MP spring (4) is weakened, damaged
or first stage is improperly adjusted.
1. The diaphragm (6) is worn or damaged.
2. The diaphragm seating surface is worn or
damaged.
3. The diaphragm clamp (3) is loose or not
torqued properly.
4. O-ring (12) on HP module body (13) is worn
or damaged.
5. The LP module body (8) is loose.
6. Safety plug (35) not seated or torqued
correctly.
1. Handwheel (26) not completely turned to
the "ON" position.
SEA-3000 LW & 4500 Technical Manual
TREATMENT
1. Replace seat disc & retainer (16).
2. Replace HP module body (13).
1. Clean or replace HP valve (9).
2. Replace LP module body (8).
3. Replace HP module body (13).
4. Replace o-ring (11).
5. Replace HP module body (13).
1. Replace MP spring (4) or check MP
adjustment using test gauge.
1. Replace diaphragm (6).
2. Replace LP module body (8).
3. Torque diaphragm clamp (3) to proper
value.
4. Replace o-ring (12).
5. Tighten LP module body (8). Check
safety wire (36) has been installed.
6. Check for damage and re-torque safety
plug (35).
1. Turn handwheel (26) to the "ON"
position.