A little background: my pool filter pump went out on me this past spring. I don't know how much power it produced, or what brand or much of anything about it. The previous owner of this pool (and house) owned an alternator repair shop, and I suspect he put that original pump motor together from spare parts in his shop.
In any case, I replaced the pump and motor (which had lasted me over 3 years) with a Hayward Maxflo VS (on a side note: I'm now on my third Maxflo VS--fortunately parts and labor have all been covered under warranty; though my faith in the brand and model is growing weaker by each replacement).
One thing I've noticed, is that if the main filter pump is running at 1500 RPM, the booster pump for the Polaris 380 will actually suck water from the return jets--apparently overpowering the main pump! This basically means that unfiltered water is pushed through my relief-valve screen being drawn from the return jets!
When running at 2400 RPM or higher, the return jets have positive pressure (when the booster is running); however I still end up with a lot of debris in the screen after a few hours of running.
Obviously, the assumption is (and maybe still true) that there are leaks in the main filter element(s); bad spider gasket, or bad o-ring in the return from the filter assembly manifold. I've check the elements and o-ring and they seem fine. I've yet to open up the valve and look at the spider gasket, but when I dump DE into the skimmer, I don't see any DE shooting back into the pool like I've seen in the past due to a filter failure. The filter does seem to clean the water; as after two weeks of no pump (after the last pump failure earlier this month), the water wasn't looking too good; but after running the new pump for 24 hours it cleared right up.
Granted, I suppose this last point doesn't prove the filter system isn't at fault, but could there be other issues I haven't considered? Is there such a thing as a booster pump being too powerful for the main pool pump thus drawing in some unfiltered water?
Thanks in advance for anyone's advice on this...