I only had a thermostat on mine until a couple of years ago when we had a few weeks where it never got above freezing, so the unit ran 24/7 and created a pretty wide swath of open water around both sides of the dock, which was problematic for us getting off the ice to shore (had to walk up from the neighbors).
Since then, I coupled the thermostat with a timer, so if the air temp is less than 32, the timer will let it run up to 9 hours (always enough to clear up everything), but just enough around the dock, and saves $$ too!
Had to scoop snow out of the boat for the commute this morning -PIG
ps: a good portion of Wicwas is frozen... if the cold temps keep up... we should see ice forming in Winni within the next couple of weeks
