This whole unit stays inside, not outside. The tank fits in the back of the Mr. Heater and therefore no chance of anything freezing up. We heated out house with propane for years before natural gas came through where I am and we never had any frozen lines. Even when it was -19 degrees F, below 0! we were just fine.I have heart from a neighbor who has a propane tank that the lines from the tank to the house can freeze during cold winter days…