Purpose of Small Tube in Center of Manifold of Old (1984) American Titan Filter

[Lawmann]

All,

I’m a new member and have a question about my manifold on a very old filter. I have an original American Products stainless steel vertical DE grid filer (60 sf) manufactured in (please don’t laugh) 1984. My manifold has cracked, and just for kicks I looked for a replacement manifold.

The current version of the manifold being sold for the American Titan filter (now made by Pentair) has an internal air bleed assembly that sticks out of the top of the manifold at an angle and is covered with mesh. Unfortunately, the clearance in the top part of my old stainless steel tank is not enough to accommodate the new manifold with the air bleed assembly.

My original manifold is made of thick plastic and does not have the newer angular internal air bleed tube. However, and this is what is puzzling me, the manifold does have a small plastic tube coming out of the center manifold but it is not covered. (A picture is attached.)




With the stainless steel top attached, the tube will extend up to and possibly touch and may go into the bottom of the external air release valve. What is the purpose of this tube? Since it is uncovered, it seems that it would suck or allow DE or debris to go back into the pool. I have cleaned and removed my filter for 30 years and have never thought much about this tube. Out of habit, I always thought the small tube was supposed to go into the bottom of the external air release valve, but this makes no sense. I wouldn’t think anything would go into the bottom of the external valve, which should remain unobstructed so it can do its job and bleed off air in the top of the filter tank. Has anyone seen such a tube in a manifold and if so, what does it do? Is it a 1984 attempt to bleed air internally?

I realize mine may now be obsolete but am curious about the tube in my manifold.

Thank you!

Glenn

 

[jblizzle]

Welcome to TFP!!!

I think it just lets the air out of the grids/manifold. But you are right that without a cover there would have been the possibility of DE/dirt bypassing the grids.

 

[Lawmann]

Thank you for such a quick reply! I know I am overthinking this but after seeing the new internal air bleed assemblies -- which I understand are supposed to allow air to be sucked or pulled into the grids and back out into the pool -- I thought the small tube in my manifold would also be on the "suction side" and pull air (even DE) back into the grids, rather than letting air out of the grids/manifold. If I end up patching the crack in my manifold just for a temporary fix, do you think I should just leave the tube sticking up and open like it has been for all these years?

PS -- Amazing forum. I wish I had found it years ago. The DE cleaning tutorial, alone, is invaluable!

 

[jblizzle]

The hose with a cover is to allow the air to rise from inside the grids and manifold to the top of the filter so you can let the air out with the release valve and thus NOT getting pushed to the pool.

The entire filter is on the pressure side there is no suction side. So I am not clear what you mean.

The DE cleaning tutorial, alone, is invaluable!

Thanks! I made it

 

[Lawmann]

This is exactly why NASA didn't hire me to work on rockets. I just had the ah-ha moment with your explanation of pressure. I was confused by a description of the internal air bleed assembly I saw online at pool center.com which said "this item allows air trapped in the tank the escape back into the pool plumbing", which is what made me think the air was going back into the pool. Your explanation makes more sense. Thank you again!