B2 Venturi knob

[MacLir]

Hi. I have an Atomic B2 that has served me faithfully for the last 9 years. It has received it's regular service and I have never had any issues with it. Yesterday, it was functioning fine at the surface pre-dive, including adjustment knob. During the dive, however, I noticed breathing becoming more difficult and found that the adjustment knob would not move. On surfacing, the knob could not be turned. Dive occurred off Massachusetts, 120 feet, 47 degree temp. The reg has previously performed flawlessly on many similar (inluding deeper, colder dives).

Any ideas regarding what may be going on with the knob?

Thanks!

 

[Scared Silly]

Sand or other grit has worked its way into the assembly. My suggestion would be take into your local shop and have them disassemble, clean, and rebuild it. You not believe the amount of sand I have found in second stages - I have found the AFC packed full of sand. A good cleaning is all they need.

 

[Atomic Aquatics]

Hi Maclir...Thank you for reaching out to us! Scared Silly has a great suggestion about the sand/sediment...This might very well be the issue with the knob itself. I would take it to the shop that has serviced your regulator so that they can remove the knob and inspect the 2nd stage. Since they are familiar with your equipment, they can focus on the issue and get it resolved quickly for you.

Thanks again all!

 

[MacLir]

Thanks all. That is what I will do.