DE in Pool and Main Drain Question

[NeilH]

I'm looking for some help with a problem I'm having. FYI, we did not install the pool. We bought our house last year and it was already here. I'm learning on the fly.

The pool has been opened for a week. Ever since then, I noticed DE has been returning to the pool. After doing a search, I saw that one common reason was a hole in the filter screens. I took apart the filter and noticed that one of the screens had a hole in it. I ordered a new screen and installed it yesterday. I also added six pounds of DE to the skimmer baskets.

I checked the pool today and the entire pool floor is covered in DE, when previously it was a light coating on the stairs by one of the returns. Before I go and replace all of the filter screens, are there any other possible reasons for this happening?

Secondly, I used the pool broom to push the DE towards the main drain but it looks like the main drain is not working. When I close the valves to the two pool skimmers, the filter pressure drops to zero. My assumption is this should not happen if the main drain is working.

Here are two pictures of my plumbing: http://imgur.com/Jd0SeeB and http://imgur.com/FfFVa

From left to right the valves are labeled: pool main drain, waterfall, spa main drain, spa skimmer, pool skimmer #1, and pool skimmer #2. To further confuse the issue, the pump on the far left, which appears to be hooked up to both the pool main drain and the waterfall, only turns on when the waterfall is on (one hour a day). Could it be set up such that the main drain only works when the waterfall is on?

Any help would be greatly appreciated.

 

[Richard320]

Yes, it appears the booster pump feeds off the main drain and returns to the waterfall. So the DE won't be caught in the filter if you sweep it into the main drain. Looks like a manual vacuum job.

DE getting past the filters can only be the multiport valve (unlikely) the screens, or the manifolds inside the filter. You didn't hear any cracking when you changed the one screen, did you?

 

[NeilH]

So if I'm understanding you correctly, the main drain does not go to the filter. The only function of the main drain is to provide water for the waterfall. If so, this is going to be a major hassle to clean up since the only vacuum I have is the Polaris 280 which works in a totally random path. Any idea what the hose faucet on top of the booster pump is used for?

Regarding the DE filters, I did not hear any cracking. Since I'll need to take the filter apart again what should I be looking for?

Thanks for the help.

 

[Richard320]

So if I'm understanding you correctly, the main drain does not go to the filter. The only function of the main drain is to provide water for the waterfall. If so, this is going to be a major hassle to clean up since the only vacuum I have is the Polaris 280 which works in a totally random path. Any idea what the hose faucet on top of the booster pump is used for?

Regarding the DE filters, I did not hear any cracking. Since I'll need to take the filter apart again what should I be looking for?

Thanks for the help.

I use the faucet on mine to water the lawn to keep CH down. I think it was installed for pressure testing.

Ask the neighbors. Maybe someone has an old fashioned manual vacuum and hose you can borrow for half an hour or so.

Inside the filter, look for anything cracked, broken, not seated properly, split, or torn.