Pump/Filter blowing sand

[kgull85]

So from what I've read on-line so far it sounds like I might have a cracked lateral or standpipe, but if that's the case I'm confused about something.

What's going on is that after I backwash and switch to rinse I get sand in the sight glass for a while, but it will eventually clear up. If I then switch to filter mode and turn on the pump sand will blow out of the outlet and into the pool for about 4-5 seconds and then stop.

What I'm confused about is that if I do indeed have a cracked lateral or standpipe then why does the sand stop blowing out after a little bit? What else might the problem be?

Thanks in advance for any help anyone can offer.

 

[Flying Tivo]

There is no way of knowing until you open the sand filter and remove the sand. Would be a nice opportunity to lube the spider gasket with magic lube.

Felipe

 

[kgull85]

Ok I guess that is my next step. What exactly is magic lube?

 

[zea3]

The problem could be the multiport valve needs a new spider gasket. A loose gasket could let some sand through in those situations. Unless you have a side mount multiport valve, you will have to take it off to open the filter, so check the gasket first. It should not be worn down or loose at any point. Any silcone pool lube will work for o-rings and gaskets.

 

[kgull85]

Sorry I never got back in here and replied, but I did indeed have a damaged lateral. Ended up replacing them all and adding new sand to the filter. Thanks for your help!

 

[Killypumpkin]

I was just coming to tell you to check your laterals. We had a cracked lateral assembly that dumped 50 lbs of sand in our pool. Sadly we opened to a swamp so we didn’t even know until we realized the pressure wasn’t building. It was horrible!

Glad all went well!