We have a weekend house and keep it heated all winter. Last winter was our first winter and we kept it at 50. It worked for us. Of course we are in Virginia, maybe not as cold as Ontario. Also I suppose it depends on if you have pipes on the north side or where wind can blow on them. Best is to turn off the water at the main, drain the pipes and keep it at around 50 degrees. That way you should have no damage.

Nancy in Virginia