POOL_N_SPA_PRO

I know this post was some time ago and I hope I can still help. With such a large pool the first thing I would ask is does this happen all season or more towards the beginning. Assuming it's happining all year and being as you have replace everything on you Polaris, it's all point toward lack of pressure. The operating pressure of a Polaris coming off a booster pump should be around 30 PSI. You may be able to purchase a wall tester from your retailer or go to Polaris' web site. The simple stuff to check before doing that would of course be: Backwash your filter and check to see if the cleaner works any better. If not there may be an obstruction in you impeller, filter, chlorinator. When was the last time the filter was inspected?? In our area a pool of this size would be quite old. Are you putting chlorine "pucks" in the skimmer?? If so you may have some calcification issues in you filter which would give you above normal pressure reading. Unless you have channeling issues in your filterwhich would do the opposite and give you a lower pressure reading & you pool would be tough to keep clear. Hope this helps.

I agree. My question would be are you shutting the pool pump off for vacuuming purposes only?? More than just synchronizing the actuators, I am of the mind that one of the valves has not be properly calibrated. If you are settting the control pane to pool mode (assuming you have a raised spillover spa) The only way water could be leaving the spa would be through the plumbing lines. Ie: Drain line in spa is still open while vacuuming but return is closed. I don't believe there is need to plumb in a check valve just yet. You should have been given operation manuals on your valves when your pool was completed, if not a simple visual check should tell you who made the valves. This manual will tell you how to change the pins inside so all valves are closed during pool mode. OR you would at least know who to call for replacement manuals. Either way since check valves usually have an o-ring inside that deteriorates, it's only a matter of time before this solution becomes a problem. Good luck!!