A furnace is a ducted warm-air or forced warm-air distribution system that heats the air in part of the house and moves it throughout your home. A furnace is comprised of the control system (thermostat and electrical controls), burners, heat exchangers, blowers, ducts, and ventilation.

When you change your thermostat to your desired temperature it sends a signal to your furnace. The heating element in your furnace warms the air and it is delivered throughout your home by ductwork. When the temperature reaches the set temperature, the furnace shuts down.

There are several types of furnaces. They all create heat and circulate it through your home. The different types of furnaces create heat with different materials. Gas, oil, coal, and electricity are all types of furnaces.

A gas furnace works by creating heat with natural gas. When the furnace is signaled on, the natural gas ignites, warming the air and distributing it through your home’s ductwork.

An electric furnace creates heat using an electrical resistance element.  

A furnace blower is a mechanism that moves the heated air into your home's ductwork.

Maintaining your furnace is very important. It not only ensures that is operating safely, but it also makes your furnace more efficient, and prevents damage. While electric furnaces are mainly maintenance-free, gas furnaces require occasional cleaning. No matter what type of furnace you have, having a preseason check done is a good idea. Also, if you've ever noticed any strange sounds, smells, or other signs while your furnace is running, shut it off, and have it looked at.