Particles coming out of the return valve

[PoolDoc]

Dirt on your filter does NOT cause vacuumed dirt to return to the pool via the pool returns.

There is ONLY one reason for this to happen: dirty water is bypassing the filter. There ARE several ways that can happen:
1. There are holes in your DE membranes (but then, DE will ALSO shoot into the pool after backwashing), OR
2. Something internal to your filter system OR your filter valve is allowing dirty water to bypass the filter, OR
3. You've got piping or a valve that allows dirty water to bypass the filter.

Cleaning your filter won't fix any of those -- though it's possible that if you disassemble the filter, clean it, and then re-assemble it, you may inadvertently correct the problem.

[Watermom]

Or maybe the pump is too powerful for the filter??

(Or is that only an issue with sand filters?)

[PoolDoc]

It's a sand filter thing. A excessive pump blows dirt THROUGH a sand filter, but blows OUT cartridges and DE membranes. In either case, not only vacuum debris would come through, DE would come through as well.

[waste]

Welcome to the Forum!

I fear you'll have to take the unit apart and find out why debris is bypassing.

I'm a little pressed for time tonight but will be back tomorrow to further explain.

[kramer840]

Hey Waste, any ideas yet?

[waste]

Sorry for the delay! (thanks for the 'bump')

Your first move is to open up the filter and see what's going on in there. Can you give me the age and model # of the filter? Sounds like you've got a 'micro-clear' or 'pro-grid' - what do you have for a multiport (how many positions does it have?)

You apparently know how to take out the grid assembly (nest) and get it back in. Please check the o-ring that seals the nest to the 'stand pipe' - it's one place that vacuumed debris can bypass the filter. Another can be the gasket in the multiport. Of course the other 'usual suspect' is the grids and/ or manifold on the nest. Have no fear, we can talk you through any of these problems

[kramer840]

Thanks for the update. I'll get you super-specifics in the next couple of days, but here's what I know about the filter off the top of my head......

It's a Hayward. As for age, no idea. We bought the house in Feb. '06 and haven't changed anything out. The people who had the house before us had the pool built in the early 70's, but I know the filter isn't that old.

For the multi-port, it has 6 positions.... filter, backwash, rinse, closed, and 2 others. Not sure of the brand.

I probably won't be able to check the inside until the weekend.