7th Option on multi-port: Sand to waste

[no fence cl pool]

I'd like a bit of help with diagnosis.
The pool is green at the moment which I'm going to treat but let's ignore that for the moment.

The filter has been in service just shy of 13 months.
Sand at the exit of the backwash plumbing (it's hard plumbed to the front yard) has been building.
Because of the great hoorah death of the old filter, I ignored it. It's probably been going on for months.

However, there's sand in the backwash plumbing right off the valve, so it's definitely from the new filter.

My thinking is it could be the wagon wheel gasket (but that looks perfectly fine) or damage / cracks to the valve (none seen)
Or it could be busted spraybars / hub.

I did install the spraybar setup properly, sinking it in water and adding sand after it was correctly placed.

The valve looks fine. I've only had it off once before to lube the gasket and everything is intact, the spring is solid, the gasket is perfectly intact.

What else could it be?
Any quick tips on draining sand out for what I think will be inevitable?

 

[duraleigh]

What else could it be?

Too much sand...possible even too little sand but I don't think so.

I also think it is possible to have too large of a pump which would create too much turbulence during backwash and throw sand out. I don't know that for a fact but I think it is possible.

 

[Bama Rambler]

It sounds like maybe too much sand as Dave suggested. Do you know exactly how much was put in it?

 

[no fence cl pool]

When I first walked into the local supply place and described when I had going on, it was pretty much "probably the laterals." I guess I'll call the spraybars laterals here on out.

Thanks for bringing up the pump. The local pool supply fellows and I discussed the pump.

It's a 1hp AO Smith WhisperFlo pump / basket Part 7-177450-03 Serial BZ01-12 Type CX, WFE - 4, 1-08-C04 (whichever part of that is relevant to add to my signature, I will; how much can I chop off?)

He seemed to think this lateral plumbing should be fine with 1/2, 3/4 or 1HP pumps.

I don't remember how many lbs of sand were added. It's around half-full of sand still. And I think that would be functionally okay. However, the valve female section goes over the male pipe part of the laterals fine and with nothing else being an apparent point of escape for the sand, I'm going to pull the sand and the laterals. A new lateral setup is in-hand.

The supply-shop-guy also mentioned importance of bottoming and centering of the lateral plumbing during install I placed it with only water in the filter body. Then I slowly added sand over it and I made sure to keep the vertical pipe centered. The supply guy said if the vert. pipe was off so much as .25", it could cause problems. I understand how the ball valve at the end of each spray bar operates and that sounds a bit pessimistic, but okay.

The only further troubleshooting I can imagine doing at this time which could be of any benefit would be to strain the backwash side of the valve to prove/disprove the too-much-pump theory. Or maybe restrict the 1.5" plumbing of the backwash so the turbulence has less opportunity to blow sand out.

 

[Bama Rambler]

Broken laterals usually puts sand back into the pool not out to waste. Are you seeing sand in the pool?

 

[no fence cl pool]

Hey, thank you. I hadn't thought of that. (Yeah, I haven't done any further work yet. )

I am not seeing sand in the pool.

If I'm reading you right.... Would a ball valve as restriction to the 1.5" backwash side help with the turbulence issue?
How much of a self-correcting of my theoretical too-much sand issue will I need to put up with? It's not a big deal to shovel up the sand in the front lawn. (never thought I'd say that, and it's not even in trade for a beach-front property!)

Your further elaboration is quite welcome, in case that's not obvious.

 

[Bama Rambler]

If there's a good possibility that the filter was over filled with sand, it will stop dumping sand out the waste after a few backwashes. There's a possibility that the spider gasket is leaking by when in waste mode.