1. Your furnace is more than 15 years old.
There’s no such thing as a furnace that never dies. According to David Kenyon of Sears Home Services, “the typical unit lasts about 15 or 20 years.” Unfortunately, in evaluating any given unit, "there's no way to know its expiration date in advance." All you can do is exercise caution as the furnace enters the final quarter of its life. If a previous owner installed the furnace, be advised that it may not be easy to determine exactly how long it's been there. Check the manual if you have it. Otherwise, "look for a serial number," Kenyon suggests, or present a photo of the unit to the company that manufactured it. Make no mistake: “It would be unwise to replace a fully functional furnace only because it’s old,” Kenyon says. Still, knowing its age may help put any performance problems in context.
2. Your energy bills have gone up.
As the furnace is one of the biggest energy consumers in modern homes, its efficiency level directly affects your bottom line. So, as winter gets underway, be sure to scrutinize your monthly energy bills. If you’re paying much more than last year—and the rates haven't risen—the explanation may be that "your furnace needs attention," Kenyon says. Newer, well-maintained appliances tend to perform at peak efficiency level; older ones usually don't. Depending on circumstances, Kenyon says, “repair may be able to deliver an efficiency boost." But if not, he says, “the increase in operating costs may be reason enough to install a new unit."
3. Your house isn't warm enough.
Feeling cold indoors even though the heat is on provides perhaps the most obvious motivation for taking a close look at your furnace. Kenyon advises, however, that "you can’t rule out the possibility of another cause.” It may feel chillier as a result of newly formed air leaks or a broken or malfunctioning thermostat. But in the absence of any alternative explanations, Kenyon advises homeowners not to push the heating system into overdrive. Instead, "bring in a professional"—especially if you notice significantly different temperatures in different rooms. “The hallmark of old, single-speed blower furnaces,” uneven heating may be the inevitable result of an increasingly outmoded technology.
4. It's abnormally dusty in your home.
You can succeed in containing dust, but no matter how much you clean, you can never get rid of it. That said, if you notice an increase in the amount of dust in your home despite your best efforts to eradicate it, don’t worry—you’re probably not going crazy. It could be, instead, that your furnace isn't doing its job to remove airborne particles from the warmed air. First things first: Check the furnace filter and, if necessary, clean or replace it. Kenyon recommends making it a habit to replace the filter every few months. If you don’t have a furnace service contract and it’s been years since you changed the filter—or if it's never been changed—“permanent damage may have been done to internal furnace components," Kenyon says.
5. Something looks, sounds, or smells off.
"A surprising number of homeowners rarely even go near the furnace," Kenyon says. But sometimes simply standing next to your furnace can tell you a lot about its condition. Check for cracks and corrosion, and in the process listen for any unfamiliar sounds. While squealing and screeching are a clue that the blower may need adjustment, other types of noises—grinding or banging—indicate the need for either repair or full replacement. Finally, Kenyon says, "pay attention to how the furnace room smells." When you start up the appliance for its first use of the season, you can expect a musty aroma, but if the smell lingers for more than a few days, schedule a service appointment right away.
6. Your furnace isn't cycling properly.
A furnace cycles on and off during the course of its normal operation. When the home dips below the temperature set on the thermostat, the furnace kicks on to bring the temperature back up. Once the thermostat reaches the target temperature, the furnace turns off, and the cycle continues from there. If the performance of your furnace gives you any reason to think it may be on its way out, track its pattern of operation. Or, as Kenyon puts it, ask yourself two questions: “Does the furnace cycle on and off very frequently? Or does it seem to run all the time?” If the answer is yes to either question, Kenyon continues, it’s a “clear sign the furnace isn’t working as designed.” Call in a qualified pro to look into the behavior.
Bad news? Seize the opportunity!
The bottom line: Numerous issues can cause a furnace to fail, temporarily or for good. If the cost of repair would be prohibitively high—or if replacement offers the only way forward—bear in mind that, although heating equipment doesn't come cheap, there’s a silver lining. Newer furnaces offer unprecedented efficiency, so you should end up saving money each month on energy bills and gradually recoup the cost of the new unit. Of course, to reap the greatest benefits from a new furnace, it must be installed correctly. For such a high-stakes project, many choose to work not with a local outfit, but with a well-established, nationwide service provider like Sears Home Services. Schedule a free in-home consultation today!
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