Above Ground Pool Filter Problem

Ok, So I have an sand filter that came with the pool when I bought the house (so no Idea how old it is). Last summer when vacuuming the dirt kept going back in through the return. So I changed the valve on the filter and replaced the sand. It seemed to have worked but I did this toward the end of summer so only really used the pool a couple of more time. Fast forward to now and I'm opening up my pool today and the dirt is once again going back through the return. What should I do? I'm at my wits end. Do you think at this point I should replace the entire filter? Oh I also replaced the pump about 2 years ago so that's good. I have a 24 foot above ground pool and the size filter I have should be big enough to handle the pool. Thanks.

What size pump do you have and what size filter? It may be that your pump is oversized for your filter. We see this all the time, especially on AG pools. Too big of a pump forces debris through the sand bed and back into the pool.

(By the way, I deleted your other duplicate post. New members' posts go into a moderation queue for one of us to approve before it appears on the forum. So, when you make a post, never fear. It will appear!)

I had this exact same problem last year. Ended up buying a new filter better suited for my pump and haven't looked back...

Welcome to to The Forum!

Have you tried adding 1/2 - 1 cup DE to the filter?

The DE will do one of 2 things

1) If you have broken internals, it will come right out of the retuns and let you know that it's time to replace parts or the entire filter.

2) If what's bypassing the filter is very fine debris, the DE will catch it and stop the problem.

A 5 lb box/ bag of DE is less expensive than a new filter and would, IMO, be the place to start. :)

I have a Hayward S-166T (100 lbs) with a HP 1.5 pump. Oh and Thanks Watermom, I thought I only posted once but I ended up using the back button on my browser and refresh so it may have submitted twice (if that makes sense).
I haven't tried the DE solution, thanks waste.

That is a pretty small filter and a pretty big pump. Can you provide the model number of the pump? 1.5HP could really be 1HP or less - There's all sorts of shenanigans surrounding pump ratings especially AG pumps.

Big Dave is right. Even the MOST up-rated 1.5hp pump is probably too big for a 100# sand filter. At a guess, I would say that your laterals in the filter have been damaged by too much pressure. There are a few solutions if that's the case:
1) Replace the filter with a bigger one, like the 200# or 250# filter--it's always better to have a filter that exceeds the pump's capacity, but I'm assuming an up-rated 1.5, not full-rated, in which case even a 250# MIGHT be too small.
2) Replace the laterals and get a smaller pump.
3) Replace the laterals and get a low-flow impeller for the pump.

BUT--try the DE test first--that's a $10-$15 investment vs the cost of a new filter or pump.

Carl