Helpful Hints, Troubleshooting Regulators

6.0HELPFUL HINTS

6.1TROUBLESHOOTING REGULATORS

POSSIBLE CAUSE

A. High Inhalation Effort at Depth:

1.Inlet filter clogged.

2.No air flowing through the dry air bleed system.

3.High pressure air supply insufficient.

4.Second stage improperly adjusted.

B. Free Flowing:

1.Intermediate pressure too high.

2.Damaged or worn H.P. piston seat.

3.Damaged or worn L.P. poppet stem seat.

4.Nicked or corroded orifice sealing.

5.Demand lever in second stage bent too high.

6.Weak spring in second stage.

7.Second stage improperly adjusted.

8.Parts in the second stage have been severely chilled due to repeated purging and have shrunk, allowing air to flow.

RECOMMENDED ACTION

Replace the filter.

Check the flow rate coming out of the one-way bleed valve 15 . If no or low air flow is detected, clean the flow element in the piston, or replace the piston.

Verify the supply air pressure. Make sure the customer had the tank valve turned all the way on.

Repeat Steps 1 through 6 in Section 5.4, Set-Up of Second Stage.

Adjust the first stage’s outlet pressure to below 150 psig. Remove shims 20 .

Replace seat (p/n 3801-5).This also gives high intermediate pressure.

Replace seat (p/n 978-9BN).

Dress the orifices in the first and second stages with a polishing stick, or replace the orifices.

Adjust or replace the lever.

Replace the spring.

Repeat Steps 1 through 6 in Section 5.4, Set-Up of Second Stage.

Allow the second stage to warm up to room temperature (this chilling will not occur in normal diving).