Originally Posted by Brother Les
Find a place that refills tanks (U-Haul) by the weight and you will know that you have a full tank. All (most, to not cause 'controversy') exchange places do not have full tanks to start with. I have asked and have been told that exchange places only have their tanks about 80% full. This was told to me by deliver drivers.
Originally Posted by Happy Vibe
You are only allowed to fill a propane tank to 80% this leaves room for expansion.
We discuss this a few times every now and again, as it can be easily confusing. A propane tank is filled to 80% of it's water capacity. This 20% void space allows for the expansion and vaporization of the gas.
This expansion void of the cylinder is figured into the propane capacity of the same cylinder. A 20 lb propane cylinder holds 20 lbs of propane, a 30 pound holds 30 pounds, etc................even with the 20% void.
OK, the major cylinder exchange companies (AmeriGas, Blue Rhino), usually only fill the propane cylinders to 75% of it's propane capacity (not water capacity)........so a cylinder that holds 20 lbs of propane would only have 15 pounds of propane when filled to 75% of propane capacity. So when you utilize these exchanges you are only getting a cylinder filled to usually 80, or 75% of it's propane capacity (or about 3/4ths).
You can look at the weight labels on these exchange cylinders, as well as the signs on the cages and it tells the propane weight. These companies had to get sued, before they started really putting this info on the signs.
Here is where we discussed the same misgivings previously (post #10), as well as how to weigh the tanks:
Hope it makes it easier to understand.