difference between pool and spa modein hayward heater?

Answer 1

Not much. There are two thermostat controls on these heaters. That switch just flips back and forth between the two. It's primary purpose is in an application where you have one set of equipment (filter, pump, heater, sanitizer) running a pool/ spa combination. You can set your fav pool temperature and lock it's maximum down with the tab on the dial and on the spa thermostat, do the same for spa temps (not over 104 degrees). The two maximums are then set, you use the function switch to flip between the two, depending on if you're using the spa or the pool. This way you don't have to hunt on the dial, to get the temp for each.