We bought a home with a pool. The first couple of weeks we made several costly mistakes including using the heater to heat the entire pool over 90 degrees. I think we paid $250 for gas that month. We also accidentally drained the spa into the pool.
The solar water heater did have an automation system, and 1 actuator which would turn the solar heat on (start pumping water up to the roof) if the air temperature was 8 degrees warmer than the pool water. The pump was an old 1 hp single speed pump and it needed to be replaced. What I needed to solve for is:
The adults like to use the spa in the evening, while the kids play in the pool during the day. Switching from pool to spa requires rotating 2 values, setting the heater temperature and starting the heaterThe pump needs to run at a higher speed if the pool cleaner is runningThe pump needs to run at a higher speed if the solar heater is onThe pump needs to run at a lower speed when only in a filter/skimmer cycle.