In the United States they were used mainly for supplemental heat for the passenger compartments of automobiles and aircraft. Some aircraft continue to use gasoline heaters.
First, fuel is brought to the heater using piping from a fuel tank, or taps into the vehicle’s fuel system. A fan blows air into a combustion chamber, and a spark plug or ignition device lights the gasoline/air mixture. A built-in safety switch prevents fuel from flowing unless the fan is working. Outside the combustion chamber, a second, larger diameter tube conducts air around the combustion tube's outer surface, and a second fan blows the warmed air into tubing to direct it towards the interior of the vehicle. Most gasoline heaters produce between 5,000 and 50,000 BTU per hour.
Gasoline heaters require electricity to operate. Heaters were made compatible with 6-volt, 12-volt, and 24-volt automotive and aircraft electrical systems. The heater requires routine maintenance, such as regular inspection of the combustion tube, and replacement of the igniter at periodic intervals.
Because gasoline heaters are required to be vented, special care must be made to ensure the vents do not leak into the interior of the automobile or aircraft. Combustion byproducts include soot, sulfur dioxide, carbon dioxide, and some carbon monoxide. An improperly adjusted, fueled, or poorly maintained gasoline heater could be dangerous. In aircraft, several gasoline heaters have been the subject of safety directives.
South Wind Heaters of the American automotive type such as the 781B as seen for sale on eBay, do not require ventilation as they work in a vacuum at 2" Hg at all engine speeds. If the vacuum is broken, the heater shuts off. They do require all of the their original components such as the fuel line kit that is attached to and draws gas from the carburetor. This is a critical item and is a calibrated emulsion tube. It can't be faked or made up at home. They are very efficient and use a negligible amount of fuel.
Gasoline heaters were commercially available on automobiles starting in the 1930s with continued use until the 1960s, when they were almost entirely replaced with heating systems using engine coolant.
South Wind heaters
First advertised for automobiles in the 1930s, the South Wind Heater was invented by Canadian Harry J. McCollum. In 1934, McCollum demonstrated his invention to the Stewart-Warner company in Chicago, and Stewart-Warner began production a short time later. By 1948, Stewart-Warner had produced more than 3 million heaters for use in automobiles, aircraft, and military vehicles.
Southwind (Stewart Warner) made the Model M978 heater for use in military vehicles in the 1950s and 1960s. Stewart Warner Southwind heaters could also be found on 1940s Fords, through early 1970s Volkswagens.
Other manufacturers over the years have included Janitrol. One manufacturer now marketing current technology gasoline and diesel fuelled heaters is the Espar corporation, of Ontario, Canada; a wholly owned subsidiary of the German company J. Eberspächer, the world's largest manufacturer of vehicle heating systems;
- South Wind heaters - warm memories of an old friend (JPG), 1972, retrieved 2009-03-01
- Lamm, Michael (1995), South Wind, AmericanHeritage.com, retrieved 2009-03-01
- Kelly Aerospace heaters, kellyaerospace.com, retrieved 2009-03-01
- How an Espar Airtronic air heater works, espar.com, retrieved 2009-03-01