Good evening troops. My mam has the above model and is a little uncertain about a few things regarding the water heater. (Cascade) She seems to think that it only works on gas and not elecky. with the cold weather coming in she would have to keep the water heater on all night to keep the frost at bay using the gas all night. This does not seem right to me. Is there anyone out there who owns this model and could spread a little on the subject please. She lives on it and is worried about things freezing up.