How much propane does your fridge use?
We keep our trailer in storage about 7 miles from home and emptying the fridge and refilling it for each trip seemed to be something I could get around. I went ahead and bought a 100W solar panel and ...
Forum Discussion
wanderingbob wrote:
For several years it has been against the law to put twenty pounds in a twenty pound tank . ASK THE NEXT TIME YA GET A FILL !
It is true (and has always been true) that propane tanks cannot be filled completely full, but must have some headspace. A 20 lb tank is designed to safely carry 20 lbs of propane, and would hold approximately 25 lbs if filled to full volume. It's certainly legal to fill them to the full rated capacity (at least here--maybe you have some strange and ill-guided local laws).
I just checked one of my tanks; it's stamped "WC 47.6", giving the water capacity; this means it holds 47.6 pounds of water if filled completely to the top. The limit is to fill (by weight) to 42% of the water capacity, which works out 20.0 pounds (well, 19.992 pounds if you ignore significant digits).
In short, a 20 pound propane cylinder can be filled with up to 20 pounds of propane legally. This only makes sense--it's why they call it a 20 pound cylinder, after all. How full it actually gets (when filled up) does vary somewhat depending on the ambient temperature, the exact calibration or lack of calibration of the OPD gizmo, scale, and/or dip tube, the precision with which the filler does his or her job, etc.; but it will be right around 20 pounds if properly done.
