Filter problems

[rosslamon]

I have a sand filter, and I've always had a feeling it wasn't doing it's job very well. I frequently have to vacuum to waste because it has never seemed to be filtering out anything. I slammed for almost 30 days last time before trying a flocculent and vacuuming to waste. While I know that the fact that there is any algae to begin with is my fault/water chemistry, I would still like my filter to work. After my 30 day SLAM i took my filter apart and realized my stand pipe was cracked. So I bought a new stand pipe, replaced the sand and started fresh. Except....I'm still pretty sure it isn't working. I know it isn't working because earlier I shocked and was vacuuming (not to waste, through the filter) and I watched what i was vaccuming shooting right back into the pool through the return jet. I really don't know what the next step is. Help? please?

 

[duraleigh]

When a sand filter can take absolutely no more debris, it goes right back to the pool.

How much debris are you vacuuming? Are you backwashing when your filter psi increases by 25%

 

[rosslamon]

I had just started vacuuming, so I'm not sure that was it. I wish it was something so simple. I frequently backwashed during my SLAM and even when I backwashed after vacuuming today it wasn't that bad. Very little if any pressure increase either.

 

[duraleigh]

Since your stand pipe was cracked do you think the laterals might be damaged?

 

[rosslamon]

I'm sorry, I should have said I bought a new stand pipe and lateral set. Whole thing.

 

[rosslamon]

Here's where my head is now. In the last few months I replaced the stand pipe, laterals, and sand. If I'm still having trouble with filtration the only thing left is the multiport, right?

 

[duraleigh]

The multiport valve only directs the flow of water....it has nothing to do with the filtration of the water.

 

[BlueByYou]

Is it possible your multiport is sending to recirculate mode?

 

[rosslamon]

I'm not sure. That's certainly possible, just bypassing the filter all together. I'm not really sure what else it could be. I'm going to make sure the sand isn't channeling by doing a deep clean, but other than that I'm not sure what to do. I don't want to take the stand pipe out again, because I'd have to vacuum out all of that sand to reuse it or toss it and get fresh just to get the stand pipe back in. That being said, a filter is pretty simple, parts wise. A tank, sand, stand pipe, laterals and multiport. Obviously the tank is fine, and i've replaced the sand, standpipe, and lateral. I just wish someone had an idea or experience with this issue. I don't want to have to call in the bad guys(pool store) hahaha

 

[duraleigh]

Inspecting the spider gasket on the multiport is pretty quick. Just unscrew the circle of stainless screws and very carefully lift off the assembly. If there is damage to the spider gasket (which could redirect the flow) it will be fairly obvious

 

[JesseSchmidt]

That MPV is not too expensive on Amazon. I was looking at them this summer, something like $80-90.