While were on the subject of artic heaters, my use with them has only been with diesel fuel only. I have a few kits around and have a small warehouse that I am going to set one up as a display model but use it to heat the buliding. I am only out there for a hour or so each morning. My questions is has anyone played with burning fitered used motor oil and a diesel mix, of should I just stay with diesel. My fuel source would come from a warm building (60 degrees +) all the time so the fuel should be warm, except on start up with left over fuel in the cold building part of the lines.. I am thinking just staying with diesel would be the best, but what do you guys think?