Hi, Vol,

I do not leave mine on. Since a circulate the water approx 8-10 hours daily, I point the evaporator into the air on days I feel I need to cool the pool. On days I don't feel the need, mine simply pivots downward into the water and I'm back to normal operation. Pretty convenient.

As an update, Raleigh had two consecutive 96+ days last week and my pool's highest temp was 84....running daytime only for 10 hours. I know you can't get something for nothing but this comes pretty darn close for me. Ran it pointed up all day yesterday 'til dark and water this AM was 79 degrees! It'll be pointed down all day today.