Furnace service.

Design Air is your #1 HVAC contractor in Missoula, MT and the surrounding communities. We are the leading company for all of your heating needs. If you need repairs, maintenance, or a brand new system installed, the technicians at Design Air are the qualified and professional crew for the job.

We provide the highest quality service for your forced air furnace or heat pump. We also aim to educate and inform our customers. Informed decisions are good decisions. We want you to feel confident we are qualified to perform the service for which you are hiring us.

How Much Money Can a New Furnace Save You?

Our AFUE energy savings calculator can help determine how much you could save on your utility bills. Simply enter your current unit's AFUE value and compare it to a newer, more efficient system. You can even customize it to better match your home's system for a more accurate calculation.

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Furnace Repair

Don’t get left in the cold! Is your furnace acting up, blowing cold air, or making too much noise? Our experienced team of professionals is here to keep your home warm and cozy. We repair all makes and models, and we will never try to sell you a service that you don’t need. Our technicians are honest and hard working, and we’re always transparent and fair about the work we do.

Furnace Replacement

Sometimes a repair is not sufficient to fix your furnace. Sometimes a new furnace is the most cost-effective and energy-efficient way to go. We will always be honest with you about a possible furnace replacement. We value our time and your money––we don’t want to perform repairs or service on an appliance that is in need of replacement.

If you do need a furnace replacement, we know how overwhelming it can be. Here are some of the frequently asked questions about furnaces that we get from some of our Missoula, MT residents:

What Are The Different Types Of Furnaces?

Single Stage: A single-stage furnace has only one stage of operation. It can either be turned on or turned off.

Two Stage: A two-stage furnace has two settings––full and half speed. This is a more efficient way to heat and provides for better comfort, because it can move the air at a slower pace.

Variable Stage or Modulating: A variable-stage or modulating furnace modulates the speed and heat output based on the temperature outside and the desired comfort level. This furnace only works as much as you need it, making this type the most energy-efficient type of furnace.

What Is AFUE?

AFUE, or Annualized Fuel Utilization Efficiency, is a measure of furnace-heating efficiency. The higher the AFUE, the more efficient the furnace.

What Size Furnace Do I Need?

We can calculate the correct size furnace for your home. The number of BTUs, or British Thermal Units, needed to heat your home is dependent on a number of variables. Contrary to what you might think, a bigger furnace may not necessarily mean more heating power for your home. Call us at Design Air, and we can set up an appointment to calculate the furnace size you might need.

Gas Furnace Replacement in Missoula, MT 59808

“Tristan and Cody did an excellent job replacing my old furnace with a new one. They were very professional and knowledgeable in answering my questions about the new furnace.” – Lee W.

Gas Furnace Installation in Missoula, MT 59802

“Design Air provided very professional service. The installation technician Tristan was polite and informative.
I would recommend this company for your HVAC needs.”

– Mike G.

'- Mike G.

Gas Furnace Replacement in Missoula, MT 59801

“job done in one day very efficiently, thank-you!”

– robert s.

'- robert s.

Gas Furnace Installation in Missoula, MT 59803

“They were professional and quick about getting my replacement furnace out. Tristan took his time to be sure that everything was installed properly and that we understood what changed and how it all worked. He was polite and professional. Thank you!”

– Kristina W.

'- Kristina W.

Gas Furnace Replacement in Missoula, MT 59802

“The 30 year old furnace at my folks place finally failed and I desperately needed it to be evaluated. I have to drive a long way to get to my folks place and the Design Air team was very accommodating to timeline/schedule. After a thorough review the tech showed me multiple concerns with the old furnace and very clearly explained why the furnace was failing. He gave me multiple options to choose from, and I decided to replace the system. A week later I met the replacement team at my folks place again and I just cannot tell you how impressed I was by the courtesy and professionalism of the team. They lined the entire floor-route from the front door to the furnace with canvas and plastic to ensure they didn’t impact the floor. They were quiet and fast and had the entire old system removed and they new system up and running by just shortly after lunch. What really impressed my was how they kept me informed of their progress throughout the morning; which was unexpected and really comforting. When they left the new furnace was working great and they gave me a great overview of what they did and how the new system would function. AND, when they were finished THE ENTIRE FURNACE ROOM WAS CLEANER THAN WHEN THEY ARRIVED… really impressive effort to go above and beyond my expectations. The team was wonderful and I just can’t say enough about the service and quality.

With respect and tremendous thanks to Griffin, Cody and Tristen.


– Devin H.

'- Devin H.

Need Furnace Service?

Contact the experts at Design Air.

Call us at 406-251-7997!