Average lifespan of furnaces is 15 to 20 years.


How long will my furnace last? You find yourself asking this question when you invest in a new furnace. No matter how good or expensive the model is, it won’t last forever. Therefore, it is essential to know the average lifespan of a furnace so you can find ways to extend its life and understand when it is due for replacement.

The Average Lifespan of Furnaces

The average lifespan of furnaces is 15 to 20 years. In some rare instances, furnaces can last up to 30 years. 

It’s worth noting that this is an average figure, which means that your furnace could last longer or less than that.  Many factors impact how long your furnace will last, and that is what you will find out in this guide. 

Factors that Impact the Lifespan of the Furnace

As mentioned, furnaces typically last between 15 to 20 years. Some brands last up to 30 years. However, you should schedule annual maintenance for your furnace to ensure all components are working properly and to detect potential issues before they get worse.

The following are factors that can impact how long (or short) your furnace will last.

Make and Model

The manufacturer and specific model of the furnace you buy can directly impact how long your furnace will last. Newer systems consist of more advanced components that are more efficient and tend to last longer. However, they also require proper maintenance to ensure those components work properly. 

On the other hand, older units have a shorter lifespan. Choose the most efficient systems when buying furnaces to ensure they will last for many years.

Furnace make and model.Frequency of Maintenance

The recommended practice is to conduct regular and annual maintenance of furnaces with the help of a professional HVAC technician. This step ensures a professional can assess your furnace for potential issues before they become worse or harder to fix. It also helps to keep every component working efficiently for seamless operation. 

The best reason to invest in frequent maintenance of furnaces is to extend the lifespan of the system.

Furnace Size

Choosing your furnace entails that you match the size of the furnace to your home. An appropriately sized system can run more efficiently. If the size of the furnace is not adequate, the system must work harder to heat your home. And when the components have to work harder, it can lead to faster deterioration. A higher rate of deterioration could significantly reduce the lifespan of the furnace. 


Hiring professionals to install your furnace is a must as it can directly impact the performance and lifespan of the entire system. Improper installation can lower the efficiency rating of the furnace, resulting in premature breakdowns and poor performance. Therefore, you should hire no less than professionals to install it if you want it to last longer.

Proper Ventilation

Excess moisture can cause the heating components to break down faster. Therefore, you must maintain proper ventilation for furnaces to maintain the right moisture level. Too much moisture can damage the heat exchanger. 

Thermostat Settings

You should set your thermostat at the most efficient level to keep the system running efficiently. According to the US Department of Energy, the ideal thermostat setting for homes in the winter is 63 degrees Fahrenheit. This thermostat setting ensures high energy efficiency and provides adequate warmth for your home. 

If the thermostat is too high or too low, the system works harder to maintain the desired temperature. By doing so, you can add wear and tear to the parts, reducing their lifespan. 

Set your thermostat at the most efficient level.Does Efficiency Rating Impact Furnace Lifespan?

Yes. The efficiency rating of the model of furnace can be a significant factor that impacts its lifespan. The rating is second to regular maintenance in determining how long your furnace will last.

When buying a new furnace, always check the efficiency rating to ensure your model will last for many years. If unsure what the best model or efficiency rating is, you can consult HVAC and furnace experts to help you make an informed decision.

Tips to Extend the Furnace Lifespan

Do you want to extend the lifespan of your furnace at home? Follow these tips to maximize efficiency and optimize the performance of the furnace.

  1. Replace the furnace filters regularly

The first step to extending the lifespan of the furnace is to clean out or replace your air filters regularly. Follow the manufacturer’s recommendations on when you should replace the furnace filters to maximize efficiency. It should be a part of your annual routine maintenance with an HVAC expert, or clean out your filters as often as needed.

When your furnace filters are clogged and dirty, the system must work harder to keep your home warm. The harder the furnace works, the shorter the lifespan of the system. It could also put the internal components at risk of dirt buildup. Excess dirt on the internal components can directly impact its performance and life expectancy. 

  1. Insulate your home

Your home plays a role in extending the lifespan of your furnace. Ensure maximum insulation in your home by regularly maintaining the ductwork and sealing the windows and doors. Insulating your home is essential to reduce heat loss and prevent cold air infiltration. Because of this, your furnace doesn’t have to work harder to maintain the ideal temperature to keep your home warm.

  1. Follow the recommended thermostat settings

Adjusting your thermostat settings is also crucial in extending the lifespan of the  furnace. Follow the Department of Energy’s recommendation on the ideal thermostat setting for your home during the winter months. It will help boost the efficiency of the furnace and extend its lifespan.

  1. Clear the furnace of any blockages

Make sure your furnace is free of clutter that can reduce the airflow for the entire system. If there are blockages, it will require your furnace to work harder to run and keep your home warm. Therefore, you must keep the area near the furnace and ductwork free to ensure proper airflow and allow it to run efficiently. 

  1. Regular HVAC maintenance

Preventive maintenance is integral to extending the lifespan of the furnace. Ensure you hire a professional HVAC technician to assess your furnace and fix any minor issues. This step can save you thousands of dollars on furnace repairs and ensure that the system runs optimally. 


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