This is the latest blue flame heater we have made, so we ran it for 20 hours to test how it would behave. Honestly this is the best heater we have built, and we are going ahead making these type of waste oil heater. Over the 20 hours didn't change from what you see in the video, never did any smoke appear in that time, and the blue flame continued to the end. As it burns so cleanly with the blue flame, it has reached the hotest from of burning, therefore all the oil has been burnt up only the piece of paper you started it with remains.
We have two of these for sale currently one with the bouncy castle fan $2500 and the other with a smaller quitter fan $1178.00.