Sand in pool after backwash/rinse

[wizzardz]

I have a Hayward 244T with top mount SP0714T valve. When I bought the place a couple years ago, I could tell the valve gasket was going out as I was having problem with water balance and leaking out to waste or recir.

I recently replaced the valve assembly since the gasket doesn't come separate. After running the pump with the new valve, the water cleared up nicely (even with all the pollen).

I decided to do a backwash and rinse. During the backwash the water in the backwash glass cleared up nicely. Once I switched it to rinse, the backwash glass half filled with sand. A good amount of sand was dumped in the pool as well, but stopped after a short bit.

I pulled the valve to check everything and all seemed fine. Ran another backwash and rinse with the same result.

Would cracked/broken laterals cause this? I was under the impression this would wash sand into the pool continually in filter setting.

Any ideas? TIA

 

[duraleigh]

No idea what's happening but you are correct a damaged lateral would dump sand continuously in most every case.

Richard 320 has a great saying...."The last thing you fixed is the thing that's broke"

I would revisit the multiport valve.

 

[wizzardz]

Any idea what to check on the valve....or perhaps even just below it? I replaced the entire valve assemble rather than trying to assemble from a new base plate. It was all self contained and pretty much remove screws, replace valve, replace screws. I'd suspect an air relief line, but I don't think this filter has one since its a top mounted valve.

 

[duraleigh]

I have had my multiport valve open EXACTLY ONE TIME so I may not be much help.

The path the water follows in the multi-port seems obvious enough (regardless of setting) so I would look at the way the seals match up....... something being not seated just right is probably the highest percentage of problems, I think.