Replacing Your Furnace

Mar 21, 2023

What to Know When Replacing Your Furnace

We only buy a furnace every 20 years, so make sure it is the right one that will help your home work for you.

We outline the top things to know and consider when replacing your home's furnace.


When should my furnace be replaced?

It is generally cost-effective to replace your furnace if your current system is less than 80 percent efficient and is at least 20 years old. If you have questions about your system, consider getting an energy audit — a great way to get unbiased information about your home’s energy use. It would also be appropriate to replace your furnace if it is approaching 20 years old and needs a major, expensive repair. 

What should I replace my old furnace with?

When you replace your old system, you can keep your family safe and lower your heating bills by looking for a furnace with two important features: 

1. High efficiency (96-plus percent AFUE)
A furnace with an efficiency rating — notated “AFUE” — of at least 96 percent ensures you are getting the most heat out of the natural gas your furnace is burning. 

2. Sealed venting
Sealed venting ensures that these gases don’t spill back into your home.

What is AFUE?

AFUE stands for Annual Fuel Utilization Efficiency. A 96 percent AFUE rated furnace converts 96 percent of the gas it uses to heat, and only 4 percent is lost through exhaust. Another way to think of it is that you get 96 cents worth of heat for every dollar you spend heating your home. Calculate the efficiency and financial savings associated with a higher AFUE furnace using the calculator linked below. 

When a furnace is done producing heat, the remaining gases can contain things like carbon monoxide. A 96-plus percent AFUE efficient furnace also have sealed venting, which means gases don’t spill back into your home, and ensures a safer, more efficient heating system. 

To fully take advantage of your new system, get a programmable or smart thermostat installed at the same time. 

What will you pay? 

Expect to pay between $5,500 and $6,200 to get a new high-efficiency furnace installed. While this price range is large to account for variables, the majority of customers we work with in our Lending Center or Energy Advisor Service spend at the lower end of this range. Installation of a new high-efficiency furnace costs more than an 80 percent AFUE furnace. However, in our cold climate, a high-efficiency furnace is a worthwhile investment. 

Check with your gas utility provider to see if they offer rebates for high-efficiency furnaces. Federal tax credits may also be available. Be sure to look into these options before you install a new system. 


 Outside Resources

AFUE Savings Calculator
Calculate the savings associated with a more efficient furnace.

HomeAdvisor Cost Guide
Use HomeAdvisor's True Cost Guide to estimate the cost of replacement in your area.

CEE's Lending Center
CEE makes it easy and affordable for homeowners to update their homes with low-interest financing.


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