I'm heating my old 1988 30ft Rv with it. On the lowest setting i have 69 degrees. 2 days of heat , burns 1 gallon of fuel. I have a weak 12 volt battery that powers it. It powers it for about 12 hrs. Very impressive heater!!!! No fumes at all. So far it works flawless. Been running non stop for about a month. So far, an amazing heater!! Have recently discovered the blower motors fail. I own 2 of these heaters and the blower motors have failed in both. However, Vevor does honor the warranty and replaced both heaters. Sadly the blower motors have failed on them as well. Not sure if vevor will warranty again..... However the replacement motors are $20.00. FYI, my heaters run 24/7 during the winter months. Its my fault, i've over worked them both.