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A natural gas furnace is a great way to keep your home warm during the cold winter months. They are handy for those in cooler climates, as this type of region will require more heat to keep a house comfortable.

But how long does a natural gas furnace last?

Read on for a rundown of some factors that affect a natural gas furnace’s lifespan and some tips for ensuring it lasts as long as possible.

Table of Contents

How Long Do Natural Gas Furnaces Last?

A natural gas furnace will last 15-20 years on average. However, if you inspect and maintain your furnace annually, it could last longer. In addition, if your local climate is not too harsh, it may not need to work as hard and could last even longer.

Replacing your furnace regularly is crucial to keeping your home warm and comfortable. It will also save you money in the long run by preventing your furnace from breaking down too often.

How Often Should You Replace a Natural Gas Furnace?

You should replace a natural gas furnace every 15 years. However, if your furnace is leaking or not working correctly, you should replace it sooner. Additionally, if you live in an area with extreme temperatures, you may need to replace the furnace more often.

Here are a few tell-tale signs that it’s time to replace your natural gas furnace:

Your furnace is leaking or making strange noises
You frequently experience cold or warm spots in your home
Your energy bills have risen significantly, even though your heating usage has remained constant
It is more than 20 years old

This YouTube video provides some insights into when to replace your furnace:

Screenshot from an animated YouTube video explaining when you should replace your natural gas furnace — Courtesy of Appliance Princess

Tips for Ensuring Your Furnace Lasts

There’s nothing worse than being in the dead of winter and realizing that your furnace isn’t working correctly. Thankfully, you can do a few things to ensure that it lasts as long as possible.

Below are a few essential guidelines to get the best lifespan out of a natural gas furnace.

Have Your Furnace Inspected Annually

One of the best things you can do for your furnace is to have it inspected annually. A professional furnace technician can check your system for any minor issues or faults that could be causing damage and leading to a shorter lifespan.

Some of the things a technician will check for include:

Cracks or leaks in the heat exchanger – a cracked heat exchanger is one of the leading causes of furnace failure. If left unrepaired, a faulty heat exchanger can cause carbon monoxide to leak into your house, putting you and your family at risk.
Rust or corrosion – over time, rust and corrosion can damage the components of your furnace, such as the blower motor or burners.

Perform Regular Maintenance on Your Furnace

Another key to prolonging your furnace’s lifespan is to perform regular maintenance. It can be as simple as cleaning dust and debris from the blower and burners or changing the filter regularly.

The following table summarizes the recommended frequencies for changing furnace filters:

Filter Size	Frequency of Replacement	Change Sooner If
1 – 2 inches (2.54 – 5.08 cm)	1 – 3 months	– You have pets – You smoke cigarettes – There is construction in your area
3 – 4 inches (7.62 – 10.16 cm)	6 – 9 months	– You have pets – You smoke cigarettes – There is construction in your area
5 – 6 inches (12.7 – 15.24 cm)	9 – 12 months	– You have pets – You smoke cigarettes – There is construction in your area

Table 1. Recommended frequencies for changing furnace filters

Source: Thomas & Galbraith Heating

Invest in Quality Parts and Materials for Your Furnace

Investing in high-quality parts and materials is one of the best ways to ensure that your furnace lasts long. Doing so will not only help your furnace run more efficiently, but it can also save you money in the long run.

Some of the best materials and parts to look for include:

High-quality filter media, such as electrostatic filters
Stainless steel burners
Variable-speed blower motors, which use less energy and run more quietly

Closeup on the Trophy Air Washable Electrostatic Air Filter — The Trophy Air Washable Electrostatic Air Filter, Courtesy of Tropy Air

Choose a Reputable Furnace Brand

When it comes to furnaces, not all brands are created equal. Some furnace brands are known for their quality and durability, while others are known for their high prices and poor performance.

To get the most out of your furnace, choose a reputable brand known for providing long-lasting, high-quality products. According to research by Consumer Reports, some of the best furnace brands to consider are Trane, Carrier, Lennox, and Rheem.

How Much Does It Cost To Run a Natural Gas Furnace?

It costs $0.35-$0.49 per hour to run a natural gas furnace. If you have a high-efficiency furnace, your costs will be lower because it will use less energy to heat your home. If natural gas prices are low, it will cost less to run your furnace.

According to the US Energy Information Administration, natural gas costs $4.38-$4.90 per million BTUs (MMBtu). Since a typical furnace uses 80,000-100,000 British Thermal Units (BTUs) per hour, running a natural gas furnace costs $0.35 to $0.49 per hour.

That said, several factors determine how much it costs to run a natural gas furnace, including the efficiency of your furnace and energy prices in your area.

For example, running your furnace year-round may be more affordable if you live in an area with low natural gas prices.

Tips for Reducing Your Furnace’s Operating Costs

As mentioned, having a high-efficiency natural gas furnace can help reduce your operating costs, but there are other things you can do to keep your natural gas bill low. These tips involve maintaining your furnace and ensuring it runs as efficiently as possible.

Below are some helpful tips for reducing your furnace’s operating costs.

Keep Your Furnace Maintained

As with any appliance, it’s essential to keep your furnace maintained if you want it to run efficiently and last as long as possible. Be sure to have your furnace serviced by a qualified technician at least once a year.

A natural gas furnace is serviced by a qualified technician

During a service call, the technician will inspect your system for any minor issues or faults that could be causing damage and wasting energy. If needed, they will also replace or clean air filters and other parts that may be causing inefficiencies.

Change Your Filter Regularly

Routinely changing your furnace filter is essential, as this can significantly impact its efficiency. Dirty filters prevent the furnace from working properly and can even cause it to overheat, damaging the system and shortening its lifespan.

As a general rule of thumb, it’s best to change your filter at least once every three months or sooner if it gets dirty more quickly. If you have pets or live in a dusty area, you may need to change it more frequently.

Invest in a Programmable Thermostat

A programmable thermostat is also a good idea if you’re serious about cutting your natural gas bills since thermostats can help regulate your home temperature and keep energy costs down.

A smart thermostat on the wall in our second net-zero home

With a programmable thermostat, you can automatically set the system to lower the temperature at night or when you’re away from home and raise it again when needed. That can help save a lot of money on your energy bills.

If you don’t have that kind of thermostat, try this Amazon Smart Thermostat. It’s Energy Star-certified, Alexa-enabled, and can be controlled from your smartphone. Besides, it’s straightforward to install, thanks to the installation guide included.

Consider a Furnace Replacement

If you have an older furnace that is no longer running as efficiently as it used to, you may want to consider replacing it with a newer, more efficient model. Although this is a significant upfront investment, it can pay off in the long run by helping you save money on your energy bills.

When shopping for a new furnace, look for one with a high Annual Fuel Utilization Efficiency (AFUE) rating. AFUE measures the furnace’s efficiency and is expressed as a percentage. The higher the AFUE rating, the more efficient the furnace will be.

How Much Energy Does It Take To Run a Furnace?

It takes 80,000-100,000 BTUs per hour to run a furnace. So if you’re heating an ample space, you may need more BTUs. Additionally, you may need more BTUs if the furnace is older or less efficient.

In general, several factors determine the amount of energy required to run a furnace, including the following:

The size of your home – if you’re heating a large space, you’ll need more BTUs per hour.
The age and efficiency of your furnace – older furnaces tend to be less efficient than newer models. So if you’re using an older model, you may need more BTUs per hour to heat your home.
The climate in your area – if you live in an environment with colder winters, you’ll need more BTUs per hour to heat your home.
Accompanying insulation – if your home is well-insulated, you’ll need fewer BTUs per hour to heat it.

Note: These are just a few factors affecting how much energy it takes to run a furnace. Ultimately, the best way to determine how many BTUs you need is to consult with a qualified HVAC technician.

The Bottom Line

Although furnaces typically last 15-20 years, several factors can affect their lifespan. To help ensure your furnace serves you long-term, keep it maintained, change the filter regularly, and invest in a programmable thermostat.

You may also consider replacing an older furnace with a newer, more efficient model. If your furnace is nearing the end of its lifespan, it may be time to start shopping for a replacement.

How Long Does a Natural Gas Furnace Last? (Costs, Energy)