How do you know when a furnace lifespan is reaching an end?

We all know this happens at some point, but it can be hard to accept. The average cost to replace a furnace, including installation, is $3,100. It could range from $2,150 to $5,900.

The average furnace life expectancy is 20-25 years.

In this article, we’ll help you prepare for the eventuality of needing to replace your old furnace by identifying and explaining the signs that it might be failing. Read on to learn more.

Warning Signs Your Furnace Lifespan is Ending

These warning signs are pretty consistent across multiple sources. When you notice one of more of them, consider yourself alerted.

1. Your Heating Bills Have Increased

This is a sign that the furnace is working much harder than it would need to if it were in good working order.

The cause could be leaky windows or air ducts. It could be worn out insulation. It also could be that the thermostat is set too high.

However, it might be that the furnace lifespan is reaching its end.

2. The House Is Chilly and the Furnace Is Only Blowing Cold Air

This could be caused by several things.

First, if you have an older furnace, check the pilot light to be sure it hasn’t gone out. If it has, relighting it should take care of things.

If the furnace is shutting on and off, it could mean it’s overheating. It also could be a blower fan malfunction, causing the furnace to heat the house sporadically or some parts to heat but not others. It could also be leaky air ducts.

Or it could be something else altogether. Whatever it is probably needs professional attention.

3. Your Furnace Is More than 15 Years Old

You can find out the age of your furnace by checking the serial number on its label. This could be tricky, though, since most serial numbers don’t list the manufacture date in obvious ways.

The best way to “decode” the date is to search the manufacturer’s website for a guide. If all else fails, contact the manufacturer directly.

4. There’s Increased Dust Coming From the Heating Ducts

This could be caused by dirt and dust build-up in air ducts. Or it could be a filter that needs to be changed.

Another possible cause, though is that your furnace is just too old. As furnaces age, they have a harder time filtering the air they heat.

5. The Pilot Light or Burner Flame Is Yellow, Not Blue (for a gas furnace)

Be aware that most modern furnaces use electronic ignitions, not pilot lights, so you should check the burner taking the necessary precautions or have it checked by a professional.

A yellow or flickering flame could be a sign of a dirty burner, signaling that the furnace might be producing carbon monoxide gas. Not only could this mean the furnace needs repair or replacement, carbon monoxide gas is also poisonous.

If you see a yellow or flickering flame, call an HVAC technician or your utility company right away!

Get That Heat Back On!

Depending on where your furnace is in the overall life of a furnace, you could be experiencing different types of problems–and for different reasons. With a newer furnace, for example, a problem could be due to a defective part.

But the more years your furnace has been serving you well, the more likely it is that it’s just reached the end of what would be considered a typical furnace lifespan.

Whatever might be wrong, if it’s more than a simple fix, such as replacing the filter, call your HVAC technician for help and advice. And, sorry to say, be prepared for the possibility that it’s time to replace your furnace.