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3 Warning Signs Your Furnace is Failing!


It’s the month of love, but maybe you and your furnace have a rocky relationship. It’s hard to let go of your furnace, but here are some signs you need to:

First of all, consider the age of your furnace. Unfortunately, unlike marriages (hopefully!) furnaces only lasts for 15 to 20 years.

We know what you’re thinking…”Hey, if it ain’t broke, don’t fix it!”

Well, that’s mostly true, but we know more than anyone that furnace technology has come a long way in the past two decades. As you may know, the efficiency of your furnace is measured is AFUE (Annual Fuel Utilization Efficiency) percentage.

In the 1990s, new regulations were created that made it so every new furnace installed had to be at least 78% AFUE. But nowadays, a new mid-range furnace has 80% AFUE, and a high-efficiency model is anywhere between 90 – 98%.

So what we’re saying here is, if your furnace is a 78% AFUE model, let’s say it should be 15% more efficient. How much would that save you?

Well, a gas furnace with an efficiency rating in the upper 70s may cost you around $2,500 per year. A modern gas furnace with an efficiency rating in the lower 90s only costs around $2,000 a year. (Both of these figures are based on Illinois’ average price of $16.75 per thousand cubic feet of natural gas, and based on our colder Hamel temps translating to more furnace use.)

Saving $500 a year, which of course means saving $5,000 over a 10-year period, is certainly nice!!

So that’s one good reason why even if “it ain’t broke,” you should fix it! But now, back to the main topic: How do you know your furnace might be failing?

Dusty Vents

One way is checking the air coming out of your vents. Does it seem dusty? Well, one culprit might be that you haven’t changed your furnace filter recently! But you know better than that!! If you’ve recently changed your filter and the air coming out is still dusty, it’s time to call a tech.

Use Good Sense

The second indicator of a furnace failure is more obvious: Has something changed in your senses? By which we mean, are you hearing odd noises like squeaking or bumping noises from your furnace, or is your furnace blowing cold air?

These are of course signs of furnace failure, but they could be more subtle too. You may hear a quiet popping noise (possible damaged ducts), or your furnace may be heating your home unevenly. When in doubt, call us!

Increased Bills

Lastly, you should keep in mind that a sudden increase in heating bills over the last year is a sign your furnace is failing.

Depending on how much attention you pay to those bills, that could be the most obvious sign of all!

If you suspect your furnace is failing or has just become old and inefficient, call ThermAll today at (509) 248-8368 or schedule an appointment online…Let our family serve your family!