I installed a Wave 6 last year before winter but we never got to use it since the weather out here on the western side of America saw very little cold in 2013. But I started it up a few times while parked in the yard and it seemed to be nice and toasty. Although I dont know how well its going to maintain "warm and toasty" in the snow. Maybe, but at the very least its going to help the furnace out considerably.