When should I replace my furnace?

You should consider replacing your furnace if it is 15 to 20 years old, needs frequent repairs, or no longer heats your home evenly. Other signs include rising heating bills, a yellow or flickering burner flame, excessive dust or dry air, and a cracked heat exchanger. A free in-home estimate will help you compare the cost of continued repairs with a new system.

What is AFUE and why does it matter?

AFUE, or annual fuel utilization efficiency, measures how much of a furnace's fuel becomes usable heat for your home. A 96% AFUE furnace converts 96 cents of every fuel dollar into heat, while many older furnaces are 80% efficient or less. Higher-efficiency models can lower heating bills, and your technician can explain which efficiency level fits your budget and home.

Is a gas furnace or heat pump better for my Knoxville home?

Both gas furnaces and heat pumps work well in Knoxville, and the better choice depends on your home's fuel source, budget, and comfort preferences. Gas furnaces deliver very warm air quickly and perform consistently during hard freezes, while heat pumps are highly efficient in East Tennessee's moderate winters and also provide cooling. Your technician can compare both during a free in-home estimate.

What size furnace do I need?

The right furnace size depends on a heat-load calculation that considers your home's square footage, insulation, windows, ceiling heights, and ductwork. An oversized furnace short-cycles and wastes energy, while an undersized furnace runs constantly and may not keep up on the coldest nights. That's why Aire Serv of Knoxville sizes furnaces during an in-home evaluation.

How long does furnace installation take?

Most furnace installations are completed in one day, often within four to eight hours. Installations that require new venting, ductwork modifications, or a gas line upgrade can take longer. Your technician will give you a time estimate during the free in-home evaluation so you can plan accordingly.

Furnace Installation and Replacement in Knoxville, TN

Dependable Heat Starts With the Right Furnace

Aire Serv of Knoxville replaces aging and failed furnaces in Knoxville homes, starting with a free in-home estimate and upfront pricing by the job, not the hour.

Free in-home furnace estimates
Financing and service discounts
Same-day service available
Diagnostic fee waived on approved repairs
Licensed technicians, fully insured

Dependable Heat Starts With the Right Furnace

Residential
Commercial

Schedule Online

Why Knoxville Homeowners Trust Us With Furnace Replacement

Accurate estimates and guaranteed work for one of your home's biggest systems.

Aire Serv of Knoxville provides free in-home estimates for furnace replacement because we don't quote heating systems sight unseen. Your technician evaluates your home's size, insulation, ductwork, venting, and gas or electrical supply, then recommends a furnace that fits. You'll receive an upfront price by the job, not the hour. Same-day service is available, which helps when an old furnace fails during a cold week. The evaluation also confirms whether your existing ductwork and venting can support a higher-efficiency furnace.
Financing helps Knoxville families replace a failing furnace right away instead of relying on space heaters through the winter. We also offer discounts for seniors, military members, veterans, first responders, and teachers, and we run local promotions throughout the year. Ask about current savings during your free estimate so you can compare furnace options with financing in mind. Many Knoxville homeowners use financing to step up to a higher-efficiency model that lowers monthly heating costs.
A furnace installation involves gas lines, venting, and electrical work, so safety comes first. Our licensed technicians handle every installation, Aire Serv of Knoxville is fully insured, and our workmanship and parts are guaranteed. Warranties are available, and every job is backed by the Neighborly Done Right Promise®. We can also install carbon monoxide detectors to add another layer of protection, and every gas connection is leak-tested before the new furnace is fired up.

How We Install Your New Furnace

A furnace installation from Aire Serv of Knoxville begins with a heat-load evaluation, so your new system is sized for your home instead of simply matched to the old unit. Your technician reviews ductwork condition, venting, and gas or electrical supply, then explains your efficiency options. On installation day, the old furnace is safely disconnected and removed. The new furnace is set in place and connected to the gas line, venting, ductwork, and electrical supply, and every gas connection is leak-tested. The technician then fires up the furnace, checks the burner flame, measures temperature rise and airflow, and confirms that the limit switches and other safety controls work as designed. Knoxville winters bring regular hard freezes, so we make sure the system reaches and holds your thermostat setting before we leave. You'll also get guidance on filter changes and fall maintenance.

Schedule Service

How We Install Your New Furnace

The Aire Serv Advantage

From tune-ups and maintenance to heater repair and air conditioning replacement, we provide services that keep the air you breathe clean and keep your home or business at the perfect temperature.

Guaranteed Upfront Pricing

We quote by the job not the hour, so you know the final price won't change with no hidden fees.
Learn more Click to Call
The Neighborly Done Right Promise^®

We'll get the job done right and ensure you are happy with our work.
Learn more The Neighborly Done Right Promise^®
We Treat Your Home Like Our Own^®

Expertly trained, background checked, and committed to respecting your home and putting you first.
Learn more We Treat Your Home Like Our Own^®
Anytime Customer Service

We're here for you 7 days a week, 365 days a year, and we always take extra precautions to safeguard your home during our visits.
Learn more Anytime Customer Service

Aire Serv of Knoxville

Aire Serv of Knoxville installs and replaces furnaces throughout Knoxville and the nearby communities of Oak Ridge, Powell, and Lenoir City. We also provide furnace installation for homes in Clinton, Halls, Heiskell, Andersonville, and other East Tennessee towns. Our licensed technicians offer free in-home estimates, upfront pricing, and financing so you can get dependable heat in place before winter sets in.

HVAC Services in Knoxville and Surrounding Areas

Aire Serv of Knoxville provides heating installation, repair, and maintenance for homes and businesses. Along with furnace installation and replacement, we offer furnace repair, heater replacement, heat pump installation, and seasonal furnace tune-ups. Commercial furnace replacement is available for local businesses, and we also install thermostats, humidifiers, and carbon monoxide detectors for a safer, more comfortable home.

Residential
Commercial

Furnace Installation Questions From Knoxville Homeowners

A new furnace should keep your home warm and safe for many winters, so it pays to understand your options. These answers cover when to replace a furnace, how to choose the right size and efficiency, how gas furnaces compare with heat pumps, and what installation involves when you work with Aire Serv of Knoxville in the Knoxville area. A well-chosen furnace can serve your family for 15 to 20 years.

You should consider replacing your furnace if it is 15 to 20 years old, needs frequent repairs, or no longer heats your home evenly. Other signs include rising heating bills, a yellow or flickering burner flame, excessive dust or dry air, and a cracked heat exchanger. A free in-home estimate will help you compare the cost of continued repairs with a new system.
The right furnace size depends on a heat-load calculation that considers your home's square footage, insulation, windows, ceiling heights, and ductwork. An oversized furnace short-cycles and wastes energy, while an undersized furnace runs constantly and may not keep up on the coldest nights. That's why Aire Serv of Knoxville sizes furnaces during an in-home evaluation.
AFUE, or annual fuel utilization efficiency, measures how much of a furnace's fuel becomes usable heat for your home. A 96% AFUE furnace converts 96 cents of every fuel dollar into heat, while many older furnaces are 80% efficient or less. Higher-efficiency models can lower heating bills, and your technician can explain which efficiency level fits your budget and home.
Both gas furnaces and heat pumps work well in Knoxville, and the better choice depends on your home's fuel source, budget, and comfort preferences. Gas furnaces deliver very warm air quickly and perform consistently during hard freezes, while heat pumps are highly efficient in East Tennessee's moderate winters and also provide cooling. Your technician can compare both during a free in-home estimate.
Most furnace installations are completed in one day, often within four to eight hours. Installations that require new venting, ductwork modifications, or a gas line upgrade can take longer. Your technician will give you a time estimate during the free in-home evaluation so you can plan accordingly.

Residential
Commercial