Furnace replacement guide: Should you repair or replace your furnace?

If you’re like most people, you probably don’t think about your furnace until it breaks down. 

The challenge with that strategy, though, is that when a breakdown happens, it’s usually not very obvious what to do. (And then you end up Googling across the internet for articles like this one.)

It’s tricky to know what your best option is—especially if you need to get warm fast. Is it worth it to replace a furnace? Or should you repair it? 

Is there a way to tell which option is better for your home and budget?

The answer to that last question: A resounding yes.

In this complete guide, you’ll get everything you need to know in order to make the best decision for you. You’ll cover:

• How long does a furnace last
• Signs you need to repair or replace your furnace
• 3 things to keep in mind when choosing to repair or replace
• Repair vs replace furnace—deciding what’s right for your situation
• The best replacement for a furnace
• How to get a new heating system installed at $0 upfront cost

And if is time to retire your old furnace? We’ll talk through the most efficient heating system option on the market.

Let’s start with an important question: How much time should you expect to get out of your furnace, anyway?

How long does a furnace last?

The average lifespan of a furnace is 15 to 20 years (1). However, this number will vary based on the type of furnace you have and how well insulated your house is.

For example, electric furnaces tend to last longer than gas ones, largely because they’re less susceptible to corrosion. A quality, well-maintained electric furnace can last up to 30 years.

On the other hand, gas furnaces have more moving parts than electric furnaces, which makes them more susceptible to wear and tear. With proper maintenance, though, you might get 20 years out of your gas furnace.

(And oil furnaces? They last up to 20-25 years (2), but generally require more maintenance than gas or electric furnaces, so your mileage may vary.)

Keep in mind: These times are averages, not predictions. 

There are always exceptions to the rule, and one of the most important factors in determining the lifespan of your furnace is the quality of care it receives. 

The single best thing you can do to extend the life of your furnace (besides maintenance) is by air sealing and insulating your home. 

This means getting an annual tune-up from a qualified HVAC technician, as well as following all the mandated upkeep requirements (you did replace the air filter recently, right?).

If you’re faithfully maintaining your furnace, there’s a good chance it will last to the upper end of its projected time range—or even longer.

And importantly, the single best thing you can do to extend the life of your furnace (besides maintenance) is help it do its job efficiently by air sealing and insulating your home. 

If your house is well insulated and air sealed, it’s already set up to keep heated air inside and reduce the load on your system. So your furnace will have a much easier (and longer!) life. 

Okay, that was a large chunk of general information. 

Now that you know how long a furnace is expected to last, let’s put all that aside and enter the real world. 

Let’s say you’re starting to notice some unsettling things about your furnace. Maybe it’s making a strange clanking noise or a funny smell. What to do? How do you know if your furnace is dying?

We’ll look at those questions now.

Signs that you need to repair or replace your furnace

Here’s a quick look at the signs that it’s time to consider a furnace repair or replacement. We’ll dig into each symptom in more detail below. (Use these links to jump ahead if needed.)

1. The cost to run your furnace is increasing each season
2. You’re regularly adjusting the thermostat to stay comfortable
3. Your furnace is making strange noises
4. Your furnace keeps turning on and off—and on again
5. The heat in your house is uneven
6. Your home is making you sick
7. Your furnace is getting up there in age

The cost to run your furnace is increasing each season

Did you just pay for the second furnace repair in two years? That’s a bad sign. 

And if your utility bills are mysteriously spiking because of increased energy usage, that’s also… not great. Any HVAC system will lose efficiency as it gets older, but if you keep pulling out your wallet for repairs or bill overages, it’s time for a major change.

Pro tip here: Energy costs are rising in general, so you might already see year-over-year increases on your bill. So you’ll need to review the amount of energy your house is using for a key indicator of efficiency changes.

Read Why is my heating bill so high? for more insight.

You’re regularly adjusting the thermostat

If you’re constantly tweaking your thermostat… well, you shouldn’t be! If your furnace is functioning correctly, you should be able to find a comfortable temperature and stick with it for a while. 

So if your furnace can’t maintain a consistent temperature, there might be a problem with the blower or the heat exchanger.

Your furnace is making strange noises

If you hear banging, popping, squealing, or grinding sounds coming from your furnace, it could be a sign that one of the major components is failing (or, you know, that your house is haunted). 

Ghosts aside, unusual furnace sounds usually indicate that there’s something loose inside the unit—and if left unchecked, it could lead to a total breakdown.

Got weird noises in your house? Do rooms suddenly turn cold? Is your house haunted—or is it just drafty? Read How to fix a drafty house permanently to find out.

Your furnace keeps turning on and off (and on and off)

If your furnace is short-cycling, something is wrong. This could be an issue with the thermostat, the blower motor, or something else.

In any case, it’s not something you should ignore, because short-cycling puts a lot of wear and tear on your furnace and that could do major damage over time.

Read Why is my heat short-cycling? to get the scoop on why your furnace is turning off and on again.

The heat in your house is uneven

Do you have hot and cold spots in your house? If so, it’s probably because your furnace isn’t evenly distributing heat. 

Uneven heating is a bit of a tricky issue, though, because it can also be a sign that air is getting in from the outside, usually due to poor insulation or lack of air sealing. 

The best way to tell if your furnace is the main culprit is change over time: If your house is normally comfortable, but suddenly develops an uneven heating issue, it’s likely that your furnace has a lot to do with it.

Your home is making you sick

If you’ve been feeling sick recently and you can’t figure out why, it might be time to get your furnace checked—and quickly. If your furnace isn’t working properly, it could be leaking carbon monoxide or other fumes into your home. These fumes can cause a range of symptoms, from headaches and dizziness to nausea and fatigue.

And in case it isn’t obvious: This kind of situation is an emergency. The moment you suspect your furnace might be making you sick, get out of the house right away and call a technician. In many localities, you can also call the fire department or your gas company directly for an immediate safety check. Better safe than sorry. 

Your furnace is getting old

Age is just a number, but when it comes to furnaces, it’s an important one. 

If your furnace is more than 15 years old, it’s time to start saving for a replacement. Even if your furnace seems to be working fine, an older unit will be less efficient (and therefore more expensive to operate) than a newer one.

By the way, if you know your furnace is old, please don’t wait until it dies completely to start thinking about a replacement. 

Aging furnaces have a bad habit of kicking the bucket on the coldest day of the year, and trying to decide on a replacement in that kind of dire situation is less than ideal and can only lead to crankiness and regret. (Not that anyone on our team would know about this.)

Keep in mind, too, that no matter how old your furnace is, if you’re having any of the other issues listed above, it’s time to give some serious thought to an HVAC overhaul. These problems won’t go away on their own, and they’ll only get worse over time.

That just leaves the question, though: What kind of HVAC overhaul do you need? Is a furnace repair enough? How do you know when to replace your furnace, anyway?

Should you repair your furnace or replace it?

This can be a tricky decision, so it really helps to break the decision down into three main considerations: economy, function, and comfort. Let’s go through each one. 

Economy: The cost of the project

This consideration seems fairly straightforward on the surface. How much will it cost to repair your furnace? How much will it cost to replace it? Pick the one that costs less. Right?

It’s actually not so easy. While it’s true that repairing a furnace might cost a little less in the short-term, it can cost you a lot of money in the long term, especially if the furnace is already near the end of its lifetime. 

One repair can lead to another repair, and—before you know it—you’ve shelled out so much money that you wish you’d simply bought a new system in the first place.

So how much do HVAC repairs cost? That really depends on where you live and what goes wrong. In general, you can expect to pay up to $250 for the initial service call, and then $50 to $100 per hour for whatever work needs to be done (not including parts)! Ouch.

One repair can lead to another… before you know it—you’ve shelled out so much money that you wish you’d simply bought a new system.

So how much is a new furnace, then?

A replacement furnace can run you up to $6,200–$9,200, depending on the kind of furnace you buy. (3) (And keep in mind: If you’re getting tired of dealing with janky furnaces, you can get an ultra-modern, top-of-the-line heat pump for $0 upfront—if your house qualifies.)

This is important, though: A major financial consideration is your furnace’s efficiency. If your furnace is older, or if it needs several repairs, there’s a pretty good chance that it’s also wasting a lot of energy. That’s likely still going to be true even after a repair. (Here are 9 signs your house is wasting energy.)

And with heating energy prices going through the roof (4), an inefficient furnace can hit you in the wallet—month after month after month.

Long story short: Avoid making the mistake that many homeowners make: Don’t assume that repairing an old furnace is automatically the cheapest option. 

If your furnace is inefficient, a ticking time bomb of HVAC repair calls, or both, going for a new heating system could save you a lot of money over the long term.

Function: How well your current furnace is working

Is your furnace able to do its job? Again, this might seem like an overly simple question. If your furnace is heating your home, then it’s working—if it doesn’t heat your home, then it’s not.

But when it comes to your home, function means more than just simple heating. Ask yourself: Is the furnace heating your home evenly? Can I easily control the temperature? 

Or, better yet: Am I perfectly comfortable everywhere in my home?

If your furnace isn’t making your home perfectly comfortable, then it’s not doing what it’s supposed to do. Full stop.

And speaking of comfort…

Comfort: How good your home feels

Comfort is about more than just heat. It’s about living in a home where the air is pure and breathable. It’s about never having to wonder, “What’s that strange smell coming from the heating system?” or “Is it carbon monoxide causing this headache?” or even “Is this furnace going to explode someday?” 

And there’s an element of comfort, too, in the luxury of being able to set room-by-room temperature controls throughout your house—and to know that your heating system will make it happen.

And—need we say it?—always wondering whether your heating system is going to make it through the winter is pretty uncomfortable.

Basically, if you’re tired of living with uneven, inconsistent heating—or if you just don’t want to think about your home heating system any more—that’s as good a reason to replace your furnace as any.

Repair vs replace furnace—here’s how to decide for your situation

That’s a lot of info! So here are some general guidelines that can help you think through this decision a bit more clearly.

You might be better off repairing your furnace if all of the below apply…

• If the furnace is less than 10 years old
• If it’s heating your home evenly—perfect temperatures in every room
• If it’s burning fuel cleanly, with ZERO smells
• If it’s been well-maintained throughout all the years of its service (here’s where it helps to have good maintenance records from any previous owners, if applicable)
• If the cost of repairs is less than 50% the cost of a replacement heating system—and the furnace is new enough that you don’t expect more repairs in the near future
• If you’re ready to help your existing furnace out (and extend its lifespan!) by air sealing your home and/or upgrading insulation

But you might be better off replacing your furnace if…

• The furnace is more than 10-15 years old 
• You have to continuously repair your furnace 
• It’s not keeping your home warm enough (that’s its job) 
• The furnace is noisy! Some furnaces naturally are—especially older models—and repairs won’t always help.
• Your energy use is higher compared to last year—and getting higher
• You’re concerned about carbon monoxide (or someone in your house has a medical condition that makes clean air a priority)
• You live in a large, old house that’s tough to heat efficiently
• Your ductwork is in shabby condition and also in need of repair
• You want more energy-efficient heating (such as a heat pump)
• You’re uncomfortable with the age or condition of your furnace 
• Or…you’re renovating your home anyway (why not get luxurious and super-efficient HVAC while you’re at it?)

Why heat pumps are the best furnace replacement

Replacing your furnace doesn’t have to mean buying a new one. 

Nowadays, in most cases it makes more sense to replace a furnace system with a heat pump. (Get a full heat pump vs. furnace comparison.)

Why? Well, heat pumps are modern, efficient HVAC machines that can both heat and cool your home—no need for a separate air conditioner. (They also purify and dehumidify your home’s air, and they do each of these jobs excellently.) 

Essentially, having a heat pump will drastically simplify your home’s HVAC situation—while also ensuring you have the best heater and AC on the market—which makes for less maintenance and greater peace of mind.

There are other big benefits to heat pumps besides simplicity:

• They’re flexible technology that can be installed almost anywhere—with or without ductwork. 
• They heat your home with fresh-smelling, constantly circulating air. 
• They work in just about every climate—including cold climates. (Learn what temperature a heat pump stops working here.) 
• They can last up to 20-25 years—if your home is well insulated and air sealed (and depending on your local climate)
• They offer zone-by-zone comfort so you can heat every room exactly to your specifications. 
• They come with zero carbon monoxide risks since they don’t burn fossil fuels in your home.

Honestly? When it comes to comfort, heat pumps are the biggest home comfort upgrade you’re likely to experience in your lifetime. (Read more about heat pump technology and why they’re the Tesla of HVAC.)

Heat pumps are also by far the most efficient HVAC system on the planet. 

In fact, they’re up to 3x as efficient as traditional heating systems (like furnaces). You might even be able to nab rebates on them from utility, state, and federal programs (and if you’re in New York, be sure to check out our rebate calculator).

Finally, heat pumps are also expert copywriters, able to woo you into finally realizing how amazing they are with their rhetorical charms.

We’re kidding. A human wrote this; not a heat pump. 

But seriously! Heat pumps are amazing pieces of technology that are being installed in more homes around the world.

And yes, they work to heat your home on super freezing cold days. They’ve been tested—and loved—in Minnesota, Switzerland, and Finland winters.

If your home qualifies, you can replace your aging furnace with a heat pump—for NO upfront cost.

Sound interesting? Read on.

We looked into every HVAC replacement alternative. Sealed seemed like the most forward-thinking option.

Stuart B., Sealed Customer

Get a heat pump furnace replacement expertly installed: $0 dollars upfront

Sealed delivers world-class heat pump furnace replacement upgrades for US homeowners. We take care of everything from start to finish:

• We hire the best experts in your area
• Create a plan tailored to your home
• And make sure you take advantage of any eligible rebates that apply to your upgrade

Put simply: We’ll do all the difficult stuff. You just tell us how you want your home to feel… and we’ll take care of the rest.

The plan doesn’t stop at heat pumps, either. If you need air sealing, duct sealing, or insulation, we’ll help you get that, too. Every home energy makeover is completely customized to your house and preferences. 

You’ll get everything you need and nothing you don’t. We’ll even tell you if you don’t need a heat pump. (Some people don’t!)

And as for the money? It’s pretty simple: You’ll pay for the work done with a flexible payment option that works best for you and your budget.

Get started by seeing if your house qualifies. It only takes two minutes.