I get asked this question here in Bozeman all the time. How long does a furnace last? We have seen furnace units that were installed in the 1950s that are still functioning and heating homes here in the Gallatin Valley, but it isn’t very common. The average warranty for modern high-efficiency furnaces is 10 years. You should expect your furnace unit to last anywhere from 10-20 years if it is maintained an repaired regularly.
We often forget to think of our furnace unit as a piece of equipment with moving parts that need to be maintained much like the parts of your car. Once a furnace has reached 10 years old, your cost of ownership is going to start increasing and typically the repair costs are going to add up quickly making it a great time to look at upgrading to a new, more efficient furnace system. The typical rule of thumb we go by is that if you take the cost of the repair and multiply that by the age of the furnace and that cost is more expensive than replacing the entire furnace system, then it is time to look at replacing the furnace to keep it heating your home in Bozeman.