Furnaces are not complicated. Essentially they draw air from a space, heat it, and then send it back. Modern furnaces are all forced-air systems. There are three basic configurations:

1. Up-flow furnaces are placed in homes with basements
2. Horizontal flow furnaces are designed for homes with crawl spaces
3. Down-flow furnaces are for homes built on concrete slabs.

Older homes may have a system that is reliant on physics. This means that it uses the fact that hot air rises and cold air sinks to its advantage. The sinking air returns to the vents and the heated air rises out into the room. Though this is extremely efficient, it does not have the immediate effect of systems that contain blowers.

However, keep in mind that this is why up-flow furnaces have longer lives. With other models, when the system shuts off the heat is contained inside the system, not allowing it to cool down as fast. An up-flow furnace allows the hot air to rise out on its own even after the system has shut off, therefore eliminating the extra wear on the unit.

Gas furnaces may be the most common and use natural gas or propane. The furnace operates the same with either. Gas is ignited by a pilot source and then blown into the room, sending the exhaust gases through vents and out of the home. Natural gas and propane only differ in one way. Natural gas is delivered through a municipal connection and propane filters from an on-site storage tank.

Electric furnaces work the same way but use heating elements to warm the air instead of fossil fuel like the others.

Just remember that air filtration is key to any system. Maintenance will never hurt.

To find out what type of furnace best fits your heating needs, call your local ARS Lafayette center today.