Furnaces are used to give you comfort by keeping your home warm at the right temperature, especially when the winter powerfully sets in. Everyone has a basic idea of how a home furnace works. However, some specifics may differ depending on the type of furnace and the type of fuel it uses to heat your home. Understanding your furnace will go a long way in troubleshooting issues promptly. It helps you rectify specific problems at the home level while also giving you an indication if you need immediate professional help. 

All furnaces contain a heat exchanger, ductwork, blower, and vent pipe. Additionally, some furnaces include an air conditioning unit responsible for cooling during the summer. Gas and electric furnaces are used widely among homeowners. Although very similar, the significant difference between the two is that gas-powered furnaces use burners fed by natural gas, and electric-powered furnaces rely on heated coils.

How Does A Gas Furnace Work


Depending on your home’s size, your furnace system may either have a single burner or dual burners. The heating process begins with the burner itself. Once the temperature falls low, it triggers the furnace to work, and the burner engages. 

Heat Exchanger

The above step drives the gas to the heat exchanger. The heat exchanger makes use of this gas and air to turn into heat, giving it an outlet in your home’s ductwork. 


While the combustion process occurs, outside air enters the system through a separate vent. The outside air mixes with heat, warming the air to the correct temperature to distribute it through the ductwork in your home.


The filtration process removes the dirt, dust and debris before it is stored in the furnace’s plenum. This provides you and your family with clean and safe air to breathe. 

How Does An Electric Furnace Work

Heat Exchanger

Understanding your furnace, either gas or electric, is not very different. Electric furnaces pull air through an inlet into the system through a heat exchanger. The electric heating elements then warm up the air. 


The blower pushes the warm air into the ductwork in your home, which distributes the air throughout your home.

Electric Elements

Electric furnaces have electric resistance heating elements. The electrically charged particles move through metal wires, producing heat. These elements are made with long wires that are wound into coils mounted inside the furnace.

Contractor, Sequencer and Transformer

These are three essential elements of an electric furnace system. The contractor controls the voltage of your furnace’s heating element, and the sequencer turns the heating element on and off. The transformer provides power for the control circuits for the contactors, sequencers and thermostat.

Irrespective of the type, understanding your furnace of how it works and provides heat in your home is essential. For any further assistance regarding any furnace, feel free to contact Capital Plumbing and Heating. We have expertise in the installation, maintenance and repair of all types of furnaces.