Perhaps late in the season for most folks, I wanted to share a heater I built to solve my problem with the propane regulator freezing and limiting the gas flow. I have been told this is more prevalent when water is in the tank - since I use Blue Rhino and exchange tanks I don't really have any control of that. Regardless of why, this heater fixes the problem. I have used it in as low as 5 degrees and bet it would still work if it was even colder. The heater is nothing more than a 200 watt personal heater (Lasko "MySpace" heater ~$18 on Amazon) that I put inside a wooden box that is set on top of the propane tank. There is a sliding top to adjust the temperature. I usually run it with the top about 1/2 open. I finally got around to painting it. The first picture is the bottom of the box looking in, the heater, and the bracket to mount it in the box. The second picture shows the heater mounted in the box. The third is the box in operation.