Hi There! This is my waste oil burner that I built to keep my shop warm while doing other projects, It consists of a 275 gallon home heating oil tank and an old furnace blower. I decided to change it up a little bit and incorporated the blower as a double duty design by using it to feed air through heat exchanger tubes And to force feed the fire fresh air for a clean, efficient and hot burn. The old propane tank I used for a reservoir holds about 15 gallons of waste oil and will give me about 3040 hours of burn time. I used a BTU calculator by room size and my increase in temperature over time that I was getting after I tested it out in my 600SQ FT concrete block garage (12FT ceilings), based on the BTU formula it's safe to say that the BTU range, depending on the amount of oil being fed to it, is around 40,000 to 45,000 BTU's. If you have any questions about my build don't hesitate to ask! Thanks for watching! Jay