What Is A Furnace?

What Is A Furnace & How Do They Work

At its core, a furnace is an appliance in your home that heats the space through the circulation of hot air. This is the primary difference between a furnace and a boiler, which heats your home using the circulation of hot water.   

An incredible amount of heat is generated on the insight of the furnace via combustion (when a fuel source like gas is involved) or electrical resistance (in the case of an electric unit), which is then circulated around the home through existing ducts and vents. In other words, your furnace is the device that creates the heat that your HVAC system uses to regulate the temperature all throughout the year.   

The Different Types of Furnaces Explained  

All told, there are a few different types of furnaces that may be present in your home. These include ones like:   

A propane furnace. Here, propane is ignited at the furnace's burner. A mechanism called a heat exchanger transfers that heat into the incoming air. The blower unit then forces that heated air into the ducts and vents, at which point it is passed along the home to heat as necessary.  

A gas unit. Also commonly referred to as a natural gas furnace, this works almost identically to a propane unit except natural gas is used for combustion. Likewise, the fuel is brought into your home via an external gas line provided by your utility company.  

An electric furnace. These types of furnaces operate using a totally different concept and work by generating heat from a series of electric heating elements. Those elements, made up of coils, are activated when electrical energy from your home is transferred into heat energy via a resistor. That heat energy is then used to warm up the incoming air, which is once again distributed throughout your home via ducts and vents.   

An oil furnace. This is again similar to a propane or gas option in that fuel is used to create heat via combustion, but the fuel in question is oil as opposed to either of those two options.   

Each type brings with it its own unique pros and cons. Gas powered furnaces, for example, are usually the most cost effective solution - but they do require access to a city gas main in order to operate. Electric furnaces are more expensive, but they're also more versatile and can be used in more areas than natural gas alternatives can.    

There are also single stage and multi-stage units for you to choose from depending on your needs. A single stage furnace is exactly what it sounds like - one that is either on or off. Multi-stage furnaces can operate at full speed or reduced speeds, which are generally quieter and are more effective at maintaining the desired temperature in a home.    

Compare the differences between boiler vs furnace in our guide dedicated to comparing the two and drawing a line where each best performs.  Get a better understanding of how do boilers work which is a convenient alternative to your old furnace.   

If you'd like to find out more information about how a furnace works, or if you have any additional questions that you'd like to discuss with someone in a bit more detail, please don't delay - contact us today.