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Extended into 2025

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Conquer the Cold this Year

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Need to Improve your Indoor Air Quality This Winter?

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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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Proudly Partnered with

Brewers
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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.

“Interstate heating CO addressed my furnace problem very efficiently. They worked quickly to send a tech, get the required parts and have it replaced. Josh L did an excellent job. He was knowledgeable and efficient.”
- Vidya A.
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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 to Lower Your Winter Heating Bill

How to Lower Your Winter Heating Bill

December 16, 2024
Winter is here. That means your family will be spending more time indoors to stay warm. Read More
What Maintenance Is Needed for a Ductless System? Changing the filter in the air conditioner. The concept of safe and healthy housing.

What Maintenance Is Needed for a Ductless System?

November 30, 2024
A ductless heating and cooling system, or a mini split, is a splendid choice for your Germantown home and a worthwhile investment. It offers many benefits, and you can enjoy them all for years to come if you maintain the system on a consistent basis. Read More
How Can I Make My Furnace Last Longer?

How Can I Make My Furnace Last Longer?

November 15, 2024
The average furnace lasts between 10 and 15 years. But did you know you can take steps to make it last longer? There is no shortcut or hack to increase your furnace’s longevity. Read More