Furnace heating element

Ask The Experts: How Does My Furnace Work?

Everything You Need to Know About Furnaces

If your home has a furnace, you know just how important it is to keep the temperature comfortable during winter. But do you know how it works? In this blog, our experts will break down the components of a furnace and explain how they work together to keep your home warm and safe all season long. Additionally, we will also discuss the importance of maintenance so your furnace can keep you cozy for years to come.

The Anatomy of Your Furnace

Furnaces use natural gas or propane to heat air that is then distributed throughout the home. The air travels through ducts, filters, heat exchangers, and fans to ensure that your home is evenly heated from room to room. Let's break down each part of this process.


Natural gas or propane is used to power your furnace. These gasses are burned in the burners inside the furnace, producing hot combustion gasses that travel through the heat exchanger system. The combustion gasses are then released safely outside your home via flue pipes.

Heat Exchangers

Heat exchangers are metal tubes inside the furnace that transfer heat created by burning natural gas or propane into the air passing over them. This hot air is then blown into your living spaces through ducts connected to vents located in various rooms within your home.


Fans blow cold air from outside into the furnace, passing over a heat exchange unit where it is heated up before being pushed back out through vents around your home. This helps circulate warm air throughout your living space quickly and efficiently, ensuring comfort for everyone!


The duct system is a series of metal tubes installed in the ceiling and walls that allows the heated air to travel through. They will enable the air to disperse into every room through the vents evenly.

Caring For Your Furnace

For your furnace to run at its best, regular maintenance is vital for multiple parts.


Filters help keep dust, dirt, pet hair, and other particles from entering your heating system and circulating throughout your home. It's essential to regularly change these filters so that air can flow freely throughout your home without being clogged by dirt and debris.

Heat Exchangers

Heat exchangers may also need occasional cleaning, as dirt can accumulate on them over time and reduce their efficiency.


It's also essential to check for any gas leaks to ensure safety in your home; if you smell gas or experience any other irregularities with your furnace, make sure you contact a professional immediately!


The thermostat serves as the “brain” of the furnace by telling the system when to turn on and off. It does this by sensing the temperature of the air in your home and comparing it to the temperature you set on the thermostat itself. When the temperature inside your house drops below the temperature, you have set on the thermostat, and it will signal the furnace, telling it to turn on. Once the temperature inside your home rises above the set point, it will send another signal to the furnace, telling it to turn off.

Why Is Maintenance Important?

All-in-all, furnaces are complex machines that require regular maintenance to keep running efficiently and safely throughout the winter. Understanding how each component works together will give homeowners peace of mind knowing their homes are being appropriately heated without sacrificing comfort or safety. By following proper maintenance guidelines outlined by professionals, homeowners can decrease energy costs while extending their unit's lifespan and upholding any manufacturer warranties they may have purchased with their system purchase.

Your Furnace Experts

At Scott Harrison Plumbing and Heating, Inc., our professionals have the knowledge and experience to install, maintain, and repair your furnace. If you have any questions about your furnace or want to schedule a maintenance appointment, contact us online or give us a call! (714) 695-5566