Product information for the Desa Tech 90580 : The Desa Tech 90580 is a portable heater with a 50,000 BTU output, making it suitable for heating large spaces. It uses kerosene or No. 1 fuel oil as fuel and has a 4.5-gallon fuel tank, which provides a long runtime. The heater has a built-in air pump that forces air through the nozzle, creating a fine spray of fuel that is ignited by a spark plug. The heater also has a fan that circulates the heated air, ensuring even distribution of warmth. The Desa Tech 90580 is easy to operate, with just a few simple controls.