A furnace is not designed to run forever—no mechanical device can do that. But modern furnaces are built to last for many years before they start to malfunction on a regular basis, cost too much to run, or simply breakdown so completely that the labor involved in getting it working again would be prohibitively expensive.
What you want to know is… how long before your furnaces reached one of these points?
The answer is, as with so many other home comfort decisions, “it depends.” We can make a few generalizations about furnace age as well as signs of a steep decline that will tell you when a furnace is near to the end.
If you have ever had to make it through an extended power outage in your home, you know how harmful they can be. They bring life to a standstill, stop most basic activities, and during the winter can leave you trapped with a freezing cold home.
