Propane Tank Sizes
Unfortunately, most propane tanks are not stamped with their size. This can make figuring out how many pounds of propane are left in the tank difficult, and leave you wondering when the tank will run out of gas. You do not need to bring your propane tank to a filling station to determine the size. Instead, perform these simple measurements to figure out what size propane tank you have. Once you know the size of your propane tank, you can use simple weight calculations to determine how full your tank is and how long it will run your appliance.
Step 1: Set your propane tank on its bottom, and measure the height from the bottom to the base of the tank's collar, the raised piece of metal that surrounds the tank's valve.
Step 2: Measure the diameter of your propane tank by encircling it with your measuring tape at its widest point.
Step 3: Compare your measurements with the following propane tank sizes: A 20 lb. propane tank measures approximately 18 inches high by 12.5 inches in diameter, and has a BTU capacity of 430,270. A 30 lb. propane tank measures approximately 24 inches high by 12.5 inches in diameter, and has a BTU capacity of 649,980. A 40 lb. propane tank measures approximately 29 inches high by 12.5 inches in diameter, and has a BTU capacity of 860,542. A 100 lb. propane tank measures approximately 48 inches high by 14.5 inches in diameter, and has a BTU capacity of 2,160,509.
Step 4: To determine the number of hours an appliance will run on your propane tank when it is full, divide your propane tank's BTU capacity by the BTU rating listed on your appliance.