turbojimmy wrote:
I've never used the fridge for more than a few days on propane so I don't know how much it uses. Since it will be occupied your friend can keep an eye on it. Heating with propane would be super inefficient long-term but it sounds like you're aware of that.
The fridge does not use a lot of propane. My rough rule of thumb is a pound a day, but in practice it's often rather less than that, depending a lot on the size of the fridge and the ambient temperature and how often the door is opened, etc. The water heater and especially furnace if used much will consume a fair bit more propane than the fridge will.