Sand in bottom of pool

[Pattington22]

I am looking for some help with an issue I am having with sand on the bottom of my pool. Toward the end of last year, I would notice some sand in the driveway when I would backwash and then some on the bottom of the pool, but not a lot. At the beginning of this year, to preempt this, I replaced the multi-port valve and the laterals. However, I still get sand in my driveway and some considerable sand in the bottom of the pool. I called Hayward for support and they noted that perhaps there was too much sand; however, it is a Hayward S-220-T and I know I added only 250lbs of sand. In terms of my process, I backwash for two minutes and then rinse for two minutes. Should this be longer? Also, I noticed the cement pad that the filter sits on is slightly unlevel; could this create even a small gap where the standpipe meets the multiport valve, which would allow some sand to enter?

Any help is appreciated.

 

[Texas Splash]

Not so sure about the level situation. Two things you didn't mention we should rule-out:
- Type of sand added? Was it #20 silica pool sand?
- When you added the sand, did you fill the vessel partially with water "before" dumping the sand in to protect the laterals from the weight of the sand?

 

[Pattington22]

Not so sure about the level situation. Two things you didn't mention we should rule-out:
- Type of sand added? Was it #20 silica pool sand?
- When you added the sand, did you fill the vessel partially with water "before" dumping the sand in to protect the laterals from the weight of the sand?

Thanks for the reply. To your questions, yes to both.

 

[Texas Splash]

Thanks for the reply. To your questions, yes to both.

Well, you seem to be rinsing plenty long enough. You mentioned the amount of sand which you added which typically is expected to be fine. I suspect it went up about 2/3 the way up the filter housing? Nothing to give you the impression it was too full? What HP is your VSP? Any chance that was a new addition that correlated to the sand either last season of this? Trying to rule-out the possibility of too much pressure if the VSP ramped-up its RPMs occasionally. If none of that seemed to apply, I would tend to go back to the inside of the filter. I suspect something/somehow is allowing sand to pass.

 

[Pattington22]

Well, you seem to be rinsing plenty long enough. You mentioned the amount of sand which you added which typically is expected to be fine. I suspect it went up about 2/3 the way up the filter housing? Nothing to give you the impression it was too full? What HP is your VSP? Any chance that was a new addition that correlated to the sand either last season of this? Trying to rule-out the possibility of too much pressure if the VSP ramped-up its RPMs occasionally. If none of that seemed to apply, I would tend to go back to the inside of the filter. I suspect something/somehow is allowing sand to pass.

When I refilled the filter, I stopped approximately 2/3 up the filter housing. For the pump, I use a Hayward TriStar variable speed pump (max 2HP) and I have 1.5" piping. After I turn the pump off to move the multiport valve, upon restart, the pump primes at 3,000 rpm (max for my GPM, I thought) for the duration of both the backwash and rinse. Perhaps this is too high a speed/pressure?

 

[Jimrahbe]

P,

Have you always had the VS pump, or did this problem start after you installed it?

I am by no means a sand filter expert, but it seems like the only thing outside of a filter issue, that would cause sand in your pool and driveway would be too much flow... What speed are you running when filtering and backwashing? Did you limit the prime speed to 3K? I think I would limit the prime speed to 2500 and see if that helps the sand issue.

Thanks,

Jim R.

 

[Pattington22]

P,

Have you always had the VS pump, or did this problem start after you installed it?

I am by no means a sand filter expert, but it seems like the only thing outside of a filter issue, that would cause sand in your pool and driveway would be too much flow... What speed are you running when filtering and backwashing? Did you limit the prime speed to 3K? I think I would limit the prime speed to 2500 and see if that helps the sand issue.

Thanks,

Jim R.

There may be a correlation between the new pump and this issue. I do not recall this occurring with my old Jacuzzi 1.5 HP. If I am not mistaken, the 3000 rpm prime speed might be the default. I will drop it down to see if that helps. Thanks!