Summer-Settings will make it so that the heater will only turn on during your preset filter cycles, and it will help set your preset filter cycles during the coolest hours of the day (when the sun is not up). Doing this will stop thermal creeping from affecting your hot tub and keep the temperature down. Don’t worry, this is normal in the valley. After completing the steps and have summer-set your spa, you'll need to do to cool the spa down by cracking the cover for about an hour or two with something small and soft: a washcloth, a sponge or a towel work well. Add a teaspoon of Spa Sanitizer 56 (because we left the top cracked for so long), and we’re done!