I'm at a loss. I'm pretty sure it's a check valve issue with my spa but for the life of me I can't locate where the valve is located. I have separate equipment for my pool and spa and looking at the layout of the spa equipment it doesn't look like there is a check valve at all. What seems to be happening is the spa will drain to the level of the pool and reading all the threads has convinced me it's a check valve. Can someone take a look at the layout and tell me I'm not crazy.
Picture one is the spa equipment layout
Picture two is the pool equipment layout
Picture one is the spa equipment layout
Picture two is the pool equipment layout
