7/23/2012 Figured out the hot tub draining issue- I think

I think I might have figured out the hot tub draining issue. I disassembled the check valve that prevents backflow of spa water back into the pool. Upon dis-assembly I noticed that glue used to bond the pipes had dripped onto the edge of the spring loaded valve which could be causing the issue.
I cleaned up the glue with a raiser-blade and some sand paper, re-assembled the valve and refilled the hot tub- Hopefully this fixes it! We'll see soon enough.

***UPDATE- STILL LEAKING
***UPDATE TO UPDATE. I swapped the valve being used for the solar with the one for the 3-way actuator and the draining issue has nearly gone away. I now lose 1/4" per day- and that's likely just from the exchange of water when the diverter changes from Pool to Spa and back to pool mode after being run for it's daily 15 min cycle to circulate, filter and chlorinate- regardless of use. Problem solved!

Glue mark on the spring flap

Blue glue drip causing the valve to improperly seal?