We tried a similar oil filled heater to heat a 200 sq ft work room and found it to be very slow to heat up and then very slow to cool down. We donated it to a thrift store. As far as heating our tiny skoolie, when we have electricity available we use a small cube heater equipped with a fan. Our bus is well insulated and the little heater set on low (750 watts) is enough heat down to about 30 degrees. If it gets colder than that I kick on the 12,000 btu propane heater. Jack