I have to admit... the programming of my ET is a bit of a mystery to me. My pool guy did it originally, and while I have made changes to satisfy my requirements, I'm not sure I could program one from scratch. Anywho... I don't have a spa, but I have two actuators. One works the cleaner, the other solar. And as Marty described, I can up my RPM during Pool Mode, for a fast skimming session, and the SWG stays on. I do use Spa mode, to keep the solar heater running without the SWG. But I thought I could set the SWG setting during Spa mode to any percentage, 0 to 100, just as in Pool mode. I don't see where the SWG is inhibited in Spa mode. I digress.
I was just wondering if johig could use the Solar feature in some way to do his bidding. When Solar engages, in Pool mode or Spa mode, I can control the SWG % and pump speed and it moves the Solar actuator. Could the ET be "fooled" into thinking it has a solar system when it doesn't, to instead run the spillover actuator(s)? When "solar" was on, the appropriate actuator would turn on the spillway (instead of sending water to the roof), and the RPMs would ramp up to the optimum spillway speed, and the SWG would stay on (just as they do for a solar system). Then it would be a matter of manipulating the solar thermostat settings, and/or roof top temp sender and pool water temp sender to fool the ET into thinking the water was always colder than what the roof could provide so whenever Solar heat was called for the ET would go into Solar mode (spillway mode), or perhaps using the ET's "Solar" button, to engage the spillway. Something like that? I can barely describe it let alone program it!! You might have to provide the proper resistors across the ET's temp sender terminals, to manipulate it into calling for Solar heat full time? You could even schedule multiple Pool mode schedules, one with "solar" and one without, to program your spillway runtime (the ET would think it's heating the pool with solar and SWG, but really only running the spillway with SWG)?
It's a stretch. I was just thinking outside the box a bit. I "fooled" my ET into thinking I have a spa when I don't, to eek out an extra feature mode I wanted. Maybe there's someway to fool it into your spillway mode by making it think you have a solar heater?