LearningAsIGo

TxPoolGuy - You were right on. The old o-ring had shrunk in size so that it was actually on the interior of the valve and not in between the two halves...it was wedged around the perimeter which is why I hadn't noticed it. Replaced with a new one, a little MagicLube and no more leak.

No doubt that is the problem then. Thanks many times over, TxPool. Hopefully I can return the favor to someone else on this board at some point. Off to the pool supply house I go.

You sir are very astutue and clearly know your pools. I only wish that I would have checked the posts yesterday afternoon. It would have saved me some headache (see below). I actually sort of figured that out on my own before seeing your reply. I noticed the other actuator and the switch that indeed was in the OFF position. I had replaced my old DE filter with a sand filter about two weeks ago. I must have inadvertantly hit that switch when doing so. I reset it and everthing works like a champ. The issue I now have is that, before noticing the other valve/switch issue, I had removed the post-filter actuator and valve top to see if there was a problem with it. It, of course was fine and I replaced everthing but I have been unable to get a really complete seal on the valve now. It's not a large leak.....really just a pinprick size. I can still run everything fine but I do need to fix it at some point. I think that the issue might be that when I removed the top, water continued flowing out of the top of the valve (pump was off). I'm wondering if the water pressure pushing upwards when trying to seat the valve top down is preventing it from getting a completely good seal. I let the water flow out for a little bit thinking that it might just be draining out of the piping between the filter and the valve but it really never slowed down. Do you have any suggestion on how to stop the water from flowing out so that I can get a good seat? I tried different multiport settings but that didn't seem to have any effect. I pulled it off and reseated it 3 times but had the same issue each time. BTW.... there was no gasket or anything between the two halves, which surprised me. Just the two hard plastic surfaces. Is there supposed to be a gasket of some sort? Thanks again for the post as you definitely know what you're talking about!

I've had one season experience with an approx. 5 year old pool at a house I purchased last spring. Pool was in pretty bad shape and I've had to change out a lot of parts on my own. The design is one where the spa is built just on top of the deck level of the pool and has a waterfall overflow the flows back into the pool under normal operation (i.e. Pool Mode). Everything had finally been working just great until last week. Now, when the system is put into Spa Mode, the Jandy actuator rotates to the proper position but it no longer causes the water to recirculate only to the spa. i.e. it continues to overflow into the pool. Any suggestions on what to check? I'm pretty capable of performing most repairs if I just know what I'm looking for. Thanks very much for any guidance.