Scenic Small Town Nestled Amid Fertile Valley In Beautiful Rural Wisconsin.

Great Financing Plans Available

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AC Struggling?
Our Team Can Help!

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Need to Improve your Indoor Air Quality This Summer?

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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.

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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!

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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.

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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.

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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.

Air Conditioner Repair in Oconomowoc, 53066-2120

“Your technician, Eric O., identified and replaced the failed part promptly. I also appreciated the prompt response of less than a day to my call for assistance.”
- Brent L.

Air Conditioner Maintenance in Mequon, 53097

“Casey was great! Arrived on time, with text notification. Upon arrival did a check of the system and provided a thorough explanation of what the potential causes were. Then, I went to the outdoor unit to investigate and, thankfully, found no serious issues. Also checked the main unit in the basement and found no issues.

Great visit!”
- Tom A.

Gas Furnace Maintenance in Brookfield, 53045

“Eric was very helpful in all he did and worked hard the entire time he was here. We had an appointment to go to and he even worked it out so that both my husband and I could go together. Much appreciated.”
- Marilyn W.
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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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Common AC Problems and Solutions

July 15, 2024
In fact, you can save between 5 and 15 percent of the energy used for your air conditioning by changing your filter in combination with other energy-saving actions. Read More
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5 Ways to Improve Your Indoor Air Quality

June 28, 2024
The reality is airborne contaminants, such as dust, dirt, and pet dander, can negatively impact the indoor air quality (IAQ) of your Wisconsin home. At Interstate Heating Co, Inc., we want you to breathe in fresh air, which is why we offer maintenance to keep your HVAC in top shape. Read More
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AC Maintenance Checklist

June 14, 2024
Be sure you take the time to perform basic maintenance regularly as well as invest in a professional AC tune-up at least once a year. According to the U.S. Department of Energy (DOE), good maintenance can save money and reduce your energy usage. Read More
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