Wondering if you really need a new furnace? We know replacing a furnace is an expensive decision, so you want to know if it is absolutely necessary or not.
Without having a trusted technician inspect your current furnace, it’s hard to say whether it can last a few more years or if it’s ready to retire now.
However, the following situations indicate that it may be time to replace your furnace:
- Your furnace is 15+ years old
- Your furnace requires frequent and expensive repairs
- Your energy bills have steadily increased
While each situation by itself doesn’t necessarily mean you need to replace your furnace right away, if two or all of them apply to you, replacement may be the best option.
Let’s look at each of these situations in more detail to help you determine whether your furnace needs to be replaced or not.
Want a quote to replace your furnace? Our Comfort Advisors can provide you with a free, upfront estimate.
Situation #1: Your furnace is 15+ years old
Unfortunately, furnaces don’t last forever. The average lifespan of a furnace is 15 to 20 years. If your furnace is over the 15-year mark, chances are it will need to be replaced soon.
Here’s why: As a furnace ages, parts will start to malfunction and fail, resulting in a loss of efficiency or a total system breakdown. If your furnace is nearing the end of its lifespan, the manufacturer warranty that covers the cost to replace faulty parts may have expired. This means you’d be totally responsible for the full cost of the replacement part, which can be very expensive depending on the part (more on that below).
Situation #2: Your furnace requires frequent and expensive repairs
Frequent and/or expensive repairs usually mean you should consider replacing your furnace altogether—especially if your furnace is older.
We usually recommend the 50% rule to our customers: If the cost to repair your old furnace is more than 50% of the cost to install a brand new system, you’re better off buying a new furnace. Instead of putting your money into an old furnace that will likely break down again, it’s more cost effective to invest in a new system.
For example, one type of furnace repair that is especially expensive is replacing a damaged heat exchanger. The heat exchanger (pictured below) is a series of metal coils that are responsible for heating your home’s air. Because the heat exchanger is such a vital part of your furnace, if it cracks, it can cost anywhere from $1,000 to $3,000+ to replace.

The heat exchanger is located in the heart of the furnace
Note: If the manufacturer warranty for your furnace has expired and you have a damaged heat exchanger, we almost always recommend replacing the entire furnace because replacing the heat exchanger is so expensive.
Situation #3: Your energy bills have steadily increased
Have you noticed higher energy bills over the past couple of years, but your heating usage has stayed the same?
If so, it could mean your furnace is approaching the end of its life. As furnaces age, they slowly lose efficiency, which means they consume more energy to provide the same amount of heat. Eventually, your furnace may get to the point where it’s so inefficient it doesn’t make sense to keep using the furnace.
When you get a new furnace, you’ll immediately notice a drop in energy costs. New furnaces are more efficient than older models, so they require less energy to heat your home. A heating expert can help you pick a furnace with an efficiency rating that matches your upfront budget and desired long-term energy savings.
Want a quote to replace your furnace?
One of our Comfort Advisors can provide you with a free, upfront estimate on the cost to install a new furnace in your home. When you work with Cooper, you can count on honest equipment recommendations and first-class customer service.
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Luke Cooper is the General Manager of the Cooper Green team and son of Gary Cooper, owner and CEO of Cooper HVAC. After years in the field, Luke took his talents to management and has helped thousands of Colorado homeowners during hot summers and frigid winters. His decade of experience in the field and guiding the company makes him one of the most knowledgeable individuals in Colorado on HVAC, plumbing, electrical and other home services.
