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How Long Should a Furnace Last?

How long should a furnace last? A properly installed, well-maintained unit can last 20-30 years. Learn what impacts longevity and how...

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How Long Should a Furnace Last

How Long Should a Furnace Last?

Sometimes you can predict how long a furnace will last depending on its size, various installation factors, and the comfort it provides. Estimates on furnace life vary. According to This Old House, they can have a 20- to 30-year lifespan, but some units may need replacement after 15 years. However, according to Bob Vila, home furnaces can be expected to last 15 to 20 years. On the high end, some furnaces have been known to last 40 years or more, although this is a rare exception.

How long should a furnace last in your home? Below, we’ll look at the factors that can impact life expectancy and the signs your furnace may be nearing the end of its life.

Factors Impacting Furnace Longevity

  • Improper Sizing: If the furnace is too large for your home, it will short cycle, which increases wear and tear that can shorten its life. Too small a furnace will also wear out by staying on too long and struggling to maintain indoor temperature. Sizing not only has to do with square footage; climate, home construction properties, and shading by vegetation need to be factored as well.
  • Poor Installation: If the fuel lines, drainage system, and other elements are improperly installed, or airflow is impeded by poorly designed and sealed ductwork, your furnace may not last as long. Air leakage from cracked ducts can cause the unit to be overworked, while issues with energy intake can damage internal components and cause a carbon monoxide leak.
  • Lack of Maintenance: Professional maintenance ensures dirty filters are replaced to maximize airflow, fans are balanced to prolong motor life, and that heat exchangers, burners, fan blades, and other parts are cleaned of dirt and buildup. Dirty parts can make the system work harder and reduce the efficiency of heat transfer. There’s also a chance your furnace can overheat.

*Usage can impact furnace life as well. It’s therefore important to think about this when setting the thermostat. According to the U.S. Department of Energy (DOE), you can save energy, and protect your furnace, by setting the thermostat to around 68℉ in winter when you’re awake. Set it lower when away or asleep. By setting it too high, the furnace will work harder.

To summarize the points above, here’s how to get your furnace to last longer:

  • Replace the air filter as recommended.
  • Schedule annual HVAC maintenance.
  • Keep it free of dust, dirt, and debris.
  • Insulate, seal, and clean ductwork.
  • Set your thermostat per DOE guidelines.

Signs Your Furnace Won’t Last Much Longer

Regardless of the actual age of your furnace, the following signs can mean it is time to think about your replacement strategy:

  • Repairs become more frequent and increasingly more expensive.
  • The furnace is buzzing, rattling, or making other unusual noises.
  • It starts to turn on and off more frequently.
  • Air output is cold, not hot enough, or rooms are heated unevenly.
  • Humidity levels are rising in your home.
  • Heating bills rise despite not using the furnace more.
  • Dust, soot, or rust are visible around the registers.
  • The heat exchanger is cracked or otherwise visibly damaged.
  • The furnace looks rusted, corroded, or cracked.

Schedule Furnace Repair or Replacement with Sky Heating & Air Conditioning

Our customers often ask, “How long should a furnace last?” Our team works to maintain and repair your furnace, so it lasts as long as possible. But our technicians also recommend when replacing it is a better option in terms of cost, comfort, and efficiency. We always consider the best long-term solution for you and your family. To determine whether you need furnace replacement, call (503) 563-2698 today!

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