I would be draining the tanks and lines if you are in danger of things freezing and doing damage. At minimum blow out the lines with air. I am in east TN and yep, its cold. Upper teens this morning. My house is heated with an electric heat pump so they do work in the cold weather. Its a bigger unit than what is on a MoHo, I know but read your manuals on their operation and understand the limitations on your units. They are not really meant to be a replacement for the propane furnace in very cold temps. They will also not get heat to the tanks and water lines, only the propane furnace is ducted for that purpose.
