Hi everyone !
I have exactly the same problem and it seems to happen to a lot of pool owners from what I can see on the forums...
I bought the house 4 months ago and there are several problems that I have to address and I kind of want to solve this one since it seems to be the easiest one.
So I have this raised spa with a spillover to the pool and the level of the spa is going down until it reaches the pool level when I turn off the circulation pump. FYI I do not have a spa by-pass line.
I already ran some tests and here are the results:
- Spillover mode (Suction valve in pool position / Return valve in pool and spa position): the level is going down when I turn the pump off.
- Pool mode (Suction valve in pool position / Return valve in pool position): the level is NOT going down when I turn the pump off.
So the problem occurs when the return valve is not in pool position only (meaning that the return to the spa is closed). I haven't tried with the spa mode yet so maybe I should do that tonight.
I replaced the check valve yesterday (not the whole valve, only the flapper assembly : http://www.amazon.com/gp/product/B00...ilpage_o01_s00 ) and the spa is still draining into the pool.
I still believe the problem is the check valve since even though the return valve (3-way automated valve) was faulty, the water in the return line should be blocked by the check valve first, am I correct ?
I think I am clear enough and I really hope we can figure it out. The only good thing is that it is a good way to learn the pool
Thank you very much