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At What Age Should a Furnace Be Replaced?


rustic old furnace

This is one of the most common questions people ask about heating equipment. Nobody wants to have their furnace die on them for good during the middle of winter. Getting ahead of permanent furnace breakdown is a smart idea. But how long does a furnace last, and what age is the right time to consider replacing one?

There’s no definitive answer. We’ve seen furnaces fail after only five years, although in those cases the system wasn’t receiving the care it needed or it was poorly installed in the first place. You can expect more years than this if you have annual maintenance for the system and always promptly arrange for repairs with furnace repair experts in Raleigh, NC as soon as you notice the trouble.

If you’re diligent about furnace care, what’s the service life estimate?

Most Gas Furnaces Last 15+ Years

The standard gas furnace should have no problem reaching 15 years of reliable service if it’s maintained properly. In fact, it may go on to 20 years. However, past the 15-year mark is where we advise people to keep a closer watch on the system’s performance. At a certain point, wear and tear will start to set in that maintenance can’t keep away.

Early indications the furnace is going into decline are a rise in heating costs and an increase in the amount of repairs the system needs. The majority of repairs for a furnace come in the last two years of its service life, so when you are spending too much each year fixing malfunctions, the best route is probably installing a new furnace.

Another caution about gas furnaces more than 15 years old is corrosion. The years of contact between combustion gas and the metal in the heat exchanger can allow the start of corrosion. This may pose a major threat if the exchanger cracks and allows natural gas to escape. At the first sign of corrosion, call for HVAC technicians and discuss an estimate for a replacement.

Most Electric Furnaces Can Last 20 to 30 Years

An electric furnace is more expensive than a gas furnace, and it isn’t as powerful. But it does have the significant advantage of an extended service life that can often reach 30 years. The reason for this longevity is that electric furnaces don’t have the stress of combustion gas, only electricity running through coils.

When an electric furnace is more than 20 years old you can start looking for indications it’s wearing down (again, high heating costs are a major warning), but it will probably take longer before it reaches the point where a replacement is the better option.

Going for High Efficiency

You may wish to replace your current furnace once it reaches 15 or 20 years even if it’s working fine. Why? Because of the options for much higher efficiency models on the market today. If you have a gas furnace with a 70% AFUE rating, replacing it with a new condensing furnace with an 98% AFUE rating is a gigantic change—using almost 30% less fuel for the same amount of heat. Even making the change from an 80% AFUE furnace is a big difference. In these cases, age won’t be much of a factor.

Comfort Master Heating & Air Conditioning, Inc. proved service throughout the Triangle Area of North Carolina. Schedule furnace repair or replacement with us.

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