Whether it’s 95° on a summer day or 25° on a winter night, the last thing you want to ask yourself is if your home’s heating or air conditioning (AC) system is on its last legs.

But it can be difficult to know whether it’s time for repair or replacement. We’re here to provide you with a place to start if you’re on the fence about what to do. 

How do I know it’s time to replace my furnace or AC? Other than your system going out, the easiest way to tell if it’s time to replace your furnace or air conditioner is age. Many experts and manufacturers suggest replacing home heating systems after 15-20 years, depending on how well-maintained the system is. 

How can I tell how old my furnace is? If you’re unsure how old your furnace is, look at the model number on the appliance. The second and third numbers represent the year the unit was made. If it’s more than 15-20 years old, it may be a good time to start shopping for newer models and a contractor to help you with installation. 

Should I replace both my furnace and AC at the same time? There are several benefits to replacing both appliances at the same time. 

• Compatibility: Furnace and AC systems are designed to work with one another. So when you replace both at the same time, your contractor can make sure everything is running as compatibly and efficiently as possible. 
• Convenience: Replacing your natural gas furnace and AC at the same time simplifies installation. Your contractor can get the job done more effectively since they can do both at the same time—often saving you time and money. 
• Comfort: There’s been a lot of innovation in home comfort in the last 15-20 years – for both furnaces and air conditioners. Newer systems often incorporate innovative features to enhance comfort by providing more consistent temperature controls, reducing hot and cold spots, and helping control humidity. 
• Cost-savings: Spire offers rebates  and financing  to help reduce upfront costs for high-efficiency natural gas furnaces — and many electric providers provide similar offers for air conditioners. Plus, when you upgrade both appliances to higher-efficiency models, you’ll likely maximize savings on your natural gas and electric bills.

It’s important to remember that it’s not always necessary to replace both units at the same time – but doing so can provide you with many benefits. To be sure, it’s a good idea to consult with a licensed contractor who can assess your unique situation and provide you with a personalized recommendation. 

Be sure to check out Spire's resources to help make replacing your furnace easier:

• Find a certified natural gas contractor using our Find A Contractor tool 
• Explore rebates to help you save energy and money
• And, ask your contractor about applying for equipment financing