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When a Furnace Goes Bad, Maybe It Needs to Be Replaced


It’s getting to be the bundling-up time of the year—Thanksgiving is over, December is here, decorations are going up, and snow will soon arrive. And if you’ve got a furnace that isn’t getting the job done, ‘tis the season to get a new one.

If you’ve kept up with my blog, you’ll know that I’m always a careful watchdog when it comes to suspicious HVAC “contractors” who are looking to get a fast buck from customers by telling them they need to get new ACs or heaters every ten years. Honest and trained technicians like the ones at Russell & Abbott will always tell you when a furnace repair in Knoxville, TN is the better option. We aren’t going to pressure you into purchasing a new system when it’s unnecessary.

But today I’m here to talk to you about when it is necessary. Don’t just take my word for it on this blog! Please call our team for an expert—and honest—opinion about that faulty furnace.

Some of the Big Warnings Your Furnace Is Ready to Retire

So what’s going on with your furnace that makes you believe it’s time to invest in a new one? Here are the ways a furnace “goes bad” that can mean it’s replacement time … or at least time to call our experts in to take a look.

It’s super old

“Old” is relative to different types of heating systems. If we’re talking about a gas furnace (and we probably are), one that has regular maintenance can last 15 years and sometimes more. Just because your furnace reaches 15 years doesn’t mean you must automatically replace it—but it does mean you should pay closer attention to malfunctions and other warning signs because the furnace will probably need to retire in the next few years.

It’s eating up your energy bills

When you take good care of your furnace with annual professional maintenance, it will take good care of you with steady heating bills. In fact, a furnace should retain 95% of its efficiency for most of its service life. But during the last year of that service life, efficiency will begin to drop, and you’ll see the difference on your bills.

You spend too much on repairs—or have too many repairs

If repairing the furnace is an annual tradition, it’s a tradition you’ll want to break. Yearly is too frequent for repairs. More than twice a year is definitely too much! There’s also the “50% Rule”: Thou shalt not repair a furnace when the cost of the repair is greater than 50% of the price of a new furnace. At that point, the money shouldn’t go toward a repair but toward a money-saving new furnace.

We find a cracked heat exchanger

If you call our technicians and we discover the furnace has a cracked heat exchanger—something must be done. Legally, we can’t leave a furnace with a cracked heat exchanger alone because it’s a safety hazard. Although we can replace the heat exchanger, in most cases cracks appear on older furnaces, and the best route forward is to have a new furnace. Not only is this more cost-effective, but it’s also better safety all-around.

Stay warm,