Tips on a Hanging Gas Furnace

Hanging, gas-powered furnaces are efficient and relatively easy to install compared to central-heating systems. They deliver heat directly into the spaces in which they're installed rather than via a system of ducts, so they are best used in large, open spaces such as garages and workshops. The location and size of the space you want to heat, as well as the amount of money you're willing to spend in order to heat it, will be the most significant factors in determining the best heater for the job.

Fuel Types

Gas-powered hanging furnaces use either propane or natural gas as fuel. Propane is a mixture of liquified hydrocarbon gases delivered to the heater from a storage tank. A pilot flame in the heater ignites the gas, which in turn heats a heat exchanger that releases heat into the room. A natural-gas heater works in much the same way, but in this case the natural gas reaches the heater through a permanently connected gas line. Propane heaters are efficient compared to electric space heaters, but natural-gas heaters are relatively less expensive to operate than propane heaters.

Heater Size

In general, you'll need a heater that can produce 30,000 BTU for every 1,000 square feet of space that you want to heat. The largest hanging propane heaters can typically produce up to 45,000 BTU, so they are capable of heating a 1,500 square-foot space. Large natural-gas heaters produce up to 75,000 BTU, making them capable of heating a 2,500 square-foot area.


Natural-gas heaters require access to a reliable supply of gas, so you must install them in spaces where a gas line is available. Because propane heaters use a relatively portable fuel source, they're better suited to locations where connecting to a natural-gas source is impractical or too expensive. You'll have to install either type of heater in a location with clear space around it according to the manufacturer's specifications so that you minimize the risk of fire.


Both propane- and natural-gas-fueled heaters use an open flame, which introduces a number of safety concerns into spaces where the heaters are used. An open flame is obviously a fire hazard if flammable materials are stored too close to the heater, but the flame is also a combustion hazard. You must ensure that combustible gases or other potentially explosive substances do not accumulate around the heater where they can be ignited by the flame. The heater's flame also produces dangerous exhaust gases, so the heater must be properly vented, and the space in which it is installed must be adequately ventilated.