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Thank You for Visiting Sussex's Top Residential and Commercial Heating and Air Conditioning Company

Reach Out Today to Get Help!

Autumn colored forrest at the edge of a lake.

Thank You for Visiting Sussex's Top Residential and Commercial Heating and Air Conditioning Company

Reach Out Today to Get Help!

geese flying at sunset.

Thank You for Visiting Sussex's Top Residential and Commercial Heating and Air Conditioning Company

Reach Out Today to Get Help!

Virtual Consultations Are Now Available!

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HEATING and COOLING

When it comes to your comfort, our Interstate Heating Co. professionals are experts. Our team is trained, certified, and ready to take care of whatever your HVAC needs may be.

RADIANT HEATING

The installation of radiant floor heat costs more initially than more conventional heating systems, but in the long run, it saves money due to lower thermostat settings and higher efficiency. Call Interstate Heating Co. to schedule a quote today!

INDOOR AIR QUALITY

Your indoor air quality (IAQ) is central to your health and comfort. Enjoy a breath of fresh air and allow our team to find solutions that improve the air quality at your home or business. Let us help keep you safe and comfortable.

SHEET METAL ROOFING

Call Interstate Heating Co. to speak with one of our certified technicians about how a sheet metal fabricated roof can be a durable, cost-effective, and on-demand solution for you.

Our Story

Continuing a Tradition of Exceptional Heating and Cooling Services

What began in a garage in 1962—with Gordy and John Cole’s commitment to offering honest, high quality HVAC service—continues today at Interstate Heating Co. in Sussex. We’ve grown to offer the latest heating, cooling, and air quality products, and our service area now covers all of southeastern Wisconsin.

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We Are a Carrier Factory

Authorized Dealer

Carrier Factory Authorized Dealers work hard for this designation. And all their experience and work is for one purpose—to create comfortable homes and satisfied customers. So when you need a new system, or it’s time to service or repair your current equipment, you can trust you’re working with the best in the business.

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We love hearing from our customers! If you’ve had us work on your HVAC system we would love to hear from you too.

“Josh is very nice to work with. He gladly takes time to explain anything you ask him about.
He replaced the heat exchanger in less time than I expected and the furnace is now running fine.”
- David G.
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Three Generations Strong

After all this time, we still follow the most basic rule of business: we treat our customers the way we want to be treated. And we know that comfort is a big part of what makes a house a home, so we make it easier to create and care for an ideal environment.

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How Do I Know When It’s Time to Buy a New Furnace? Mature adult woman carrying firewood.

How Do I Know When It’s Time to Buy a New Furnace?

November 8, 2023
Nobody wants a problem with their furnace—but even the most efficient systems have to be replaced at some point. Read More
Video - Indoor air quality is important to your family’s health and well being. Family sitting at kitchen table eating dinner.

Video – Indoor air quality is important to your family’s health and well being

October 25, 2023
Air quality in your home is important to your family’s health. Having the right humidity levels, changing your filters regularly and installing air-cleaning or filtration systems like UV lights and air scrubbers. Read More
5 Tips to Improve Your Indoor Air Quality This Fall - Lady Wrapped up in a Blanket.

5 Tips to Improve Your Indoor Air Quality This Fall

October 4, 2023
Get ready for cooler weather here in Sussex—fall is here! Read More