How Long Do Furnaces Last?

When you're asking how long do furnaces last, the short answer is that most furnaces last somewhere between 15 and 30 years. But really, it just depends on the type of furnace—and how hard it’s had to work over the years.

What Is the Average Lifespan of a Furnace?

The average furnace lifespan often comes down to the fuel source. A gas furnace lifespan is typically around 15–20 years, while an electric furnace lifespan can reach 20–30 years. Oil furnaces generally fall somewhere between the two.

Those numbers are useful starting points, but they're not guarantees. You also have to consider how the equipment has been used. A well-maintained furnace can definitely outlast the average. On the other hand, a system that’s poorly sized for the property, or one that’s been heavily used, will likely need to be replaced sooner.

What Factors Affect How Long a Furnace Lasts?

Age is only part of the equation. You’ve got several factors to think about, and any one of these aspects can influence how quickly a furnace wears out:

·      Maintenance: Regular professional maintenance can help take care of minor problems before they become major failures

·      Installation quality: Your furnace will be less likely to go through unnecessary wear when it’s been installed correctly from the start

·      Usage: A furnace that’s constantly running in long, cold winters gets more operating time than one in a mild climate

·      Sizing: The furnace needs to be the right fit for the home’s square footage and layout

·      System condition: If you have multiple parts that are repeatedly needing repaired, that could be a sign that the overall system is on its way out

Does Furnace Size Affect Its Lifespan?

Yes. Proper sizing is crucial because a furnace that’s too small might need to run for long stretches and still struggle to meet the temperature you want. What’s more, a furnace that's too large for your home may end up reaching the thermostat setting quickly, but then it will shut off and then likely need to restart more often. That's called short cycling, and a system that goes through repeated starts and stops can experience a lot of additional wear over time.

If you're shopping for a new unit, be sure to take a look at the home's actual heating requirements. Opting to buy the largest furnace won’t necessarily do you any favors, and obviously a unit that’s too small won’t be a good fit either.

What Are the Signs It's Time to Replace Your Furnace?

There isn't one magic age when every furnace needs to be replaced. A furnace that's 18 years old won’t automatically be ready for the scrap pile. Assuming it's operating well and hasn't been too expensive to maintain, you might still have some useful life left. Of course, if you have an older furnace that’s been needing more frequent repairs, that might not be worth keeping—even if it technically still works.

You’ll want to consider your system’s specific combo of age, performance, and repair costs to determine the best path forward. Some common signs it's time to replace a furnace include:

·      It's 15–20 years old or older. Age alone doesn't mean failure, but an older furnace is more likely to need repairs.

·      Needing repairs more often. One repair isn't necessarily a reason to replace the system, but repeated service calls are another story.

·      Repair costs are adding up. If the estimate for a major repair is roughly half the cost of a new furnace, it might make more financial sense to go with a replacement.

·      Energy bills are increasing. A drop in heating efficiency can be especially problematic as equipment gets up in years.

·      Heating is inconsistent. Rooms that aren't heating evenly might indicate that the system isn't performing like it once did.

·      The furnace is making unusual noises. New rattling, banging, squealing, or other strange noises should be checked out to make sure everything is running like it should.

·      You notice unusual odors. You always want to be careful with fuel-burning equipment, so schedule a service call if something seems “off.”

When Should You Replace a Furnace Instead of Repairing It?

If an older furnace needs a relatively inexpensive repair but otherwise works just fine, then repairing it can be perfectly reasonable. But the decision becomes more difficult when you're dealing with a major repair on an aging system.

Your system’s current performance is the major player to the equation. A 17-year-old furnace that needs its first minor repair is a different situation from a 17-year-old furnace that has needed several expensive repairs in recent years. How much longer are you realistically expecting the equipment to last? Putting a good chunk of money into an older furnace might not be worth your trouble if another major component could fail soon after that repair.

Where Can You Find a Reliable Replacement Furnace?

If you’re thinking your furnace has reached the end of its useful life, the next step is to find the right replacement—without overpaying. That's where Surplus City comes in.

Surplus City has been supplying brand-name HVAC equipment since 1975. We offer brand-new, never-installed equipment from all of today’s major manufacturers:

·      American Standard

·      Bryant

·      Carrier

·      Trane

·      Goodman

·      Lennox

·      Payne, and others!

Since we buy directly from manufacturers, we’re able to offer competitive pricing without the traditional distributor markup. Plus, we keep equipment in stock. That means it’s ready to ship, so you won’t be left waiting on a backordered furnace when you’re under the clock and need a replacement.

Eligible new equipment is also available to purchase with our 30-day warranty program for some extra peace of mind.

If you're ready to replace an aging furnace, start by finding the right size and heating capacity for your home or project. Then browse our available inventory to compare your options. And if you have any questions along the way, we’re here to help: (765) 482-7000.