KJIsaacson

Indeed. Thanks again. In addition, the reading and video watching I did before installing the actuator helped immensely. I had the cams set perfectly before the install, and it worked as desired as soon as I powered up.

Imagine my embarrassment! I just discovered my own mistake, and I'm so sorry to have wasted your time. I just found that when I switch to spa mode, I can and should close off the pool drain and skimmer as I open the spa drain. This, of course, causes more water to be drawn from the spa and eliminates the overflow from the spa into the pool. My mistake was rotating the spa drain diverter valve a full 180 degrees instead of just 90 degrees. The previous actuator was obviously set for the proper 90 degree rotation, and I'll be sure to set the new one that way. Again, thanks for your help and sorry for wasting your time! Best.

Waterbear, first I want to thank you for your help and the attention you're giving to my issue. I'll clarify one thing that I did by way of typo in my FWIW remark. I meant to say IF ieave the spa drain valve open when the pool is off, the spa drains into the pool. That is not my practice. It was simply a way to check whether the valve was actually opening the spa drain. It does. If the pump is off, and I open the spa drain, the spa drains, and it does so rather quickly. To answer your other questions: Normal pool operation: When in pool mode: Water leaves the pool through the pool drain and the skimmer (as shown in the accompanying picture. The inlet labeled "To spa jets" is closed while in pool mode. NOTE: the diverter valve that controls the spa drain is usually a valve actuator. It "went" a few days ago, and I'm replacing it. Normally, it would automatically rotate 180 degrees from the position shown in the picture when switched from pool mode to spa mode. Right now, I'm doing that manually. Water comes into the spa by way of a single inlet, labeled "To spa overflow". Water also enters the pool by way of floor pop ups (labeled in picture). The result: Water overflows the spa into the pool, as desired. When in spa mode: Water leaves the spa because the spa drain is now open. Water continues to leave the pool through the pool drain and skimmer. (I can manually shut either the pool drain or the skimmer, but not both. This has been the case for years. It stays in the position show (taking water in from both pool drain and skimmer, while in either pool mode or spa mode.) Water comes into the spa by way of spa jets (labeled). No more "in" through spa overflow or floor pop ups. As for the brand/model of the automation, all is controlled by a Waterways Plastics Oasis Pool and Spa control. The actuator valves are Hayward GVA24. There are two actuators. One that opens/closes the spa jets or spa overflow/pool floor pop ups (as shown), and the other that opens/closes the spa drain (controlled manually right now, but to be replaced). As previously stated, all was working well, with these same valve settings, until a few days ago. I can confirm that the valve controlling the spa drain is indeed working. I manually turn it, and I can hear the water flow changing. Similarly, the valve controlling the spa jets into the into the spa is working. I'm stumped and would appreciate any further thoughts you might have! Thanks again.

Thanks for the quick response. FWIW, I leave the spa drain valve open when the pool is off, the spa drains into the pool. This suggests that the drain *is* opening, doesn't it?

As the title says, my spa continues to overflow into my pool, even in spa mode. The valves are properly set, with the actuator-contolled spa drain open and the actuator-controlled spa return open. This is the exact setup that worked correctly until a few days ago, when I had a new heater installed. No valve settings were changed when the heater was installed. Any ideas why the spa continues to overflow? Thanks.