how long does 20 pounds of propane last
One pound of propane will produce 21,622 BTU's. 20 pounds of propane will produce 432,440 BTU's. A heater that produces 80,000 BTU's per hour will produce heat for almost 5 1/2 hours.he MH80CV, part of the Mr. Heater Contractor Series, is a 30,000-80,000 BTU Propane Convection heater. The MH80CV provides reliable heat for areas up to 1900 sq. feet. It wil â¦ l operate for up to 14 hours on a 20-lb propane tank.