Your furnace is at least 16 to 20 years old.
The average lifespan of most furnaces today is between 16 and 20 years. Ideally, you won’t ever find out the actual lifespan of your furnace because then you’d be living without heat until you get your furnace replaced. While age is far from the only indicator that your furnace may be reaching the end of its life, it is a good starting point for those who are concerned about the health of their heating system. If your furnace is pushing the envelope of a couple of decades, you should probably consider replacing it within the next few years.
Your gas and electricity bills are going up.
While some increase may be attributed to rising gas and electric prices, the age of your furnace is not something that should be overlooked. The older your furnace gets, the longer it will likely run in order to provide your home with the same amount of heat. By investing in a new furnace, you may be able to reduce your gas and energy bills, saving some money that can be put toward the new heating unit.
Your last furnace repair bill exceeded $500.
If you are looking at having to put more than $500 into your current unit or you have already spent close to that amount in repairs, its typically recommended to start shopping around for other options. Yes, replacing your furnace is expensive, but putting it off until its too late can cause you a lot more discomfort and a much bigger bill than your trouble will be worth.