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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.


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!


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.


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.


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.


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 Sussex, 53089

“Josh was on time for the service call, diagnosed the problem and resolved it very quickly. Very knowledgeable and very polite.”
- Bill H.

Air Duct Maintenance in Waukesha, 53189

“Josh was very informative and professional when changing the filter in our AprilAire.”
- Natalie G.

Thermostat Installation in Sussex, 53089

“Chris was a very pleasant man great experience”
- David K.

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.

Video - Replace Your Air Filter.

Video – Replace Your Air Filter

May 17, 2023
Change your HVAC filters regularly, as recommended, which is usually at least every three months. A good HEPA filter will catch the particles before they reach your lungs. Read More
The love between a mother and daughter is forever: a smiling woman embracing her mother while they are looking away.

What Are Zone Control Systems?

May 3, 2023
If you have a large home with multiple stories or a large household with family members who prefer different temperatures, consider installing a zone control system. Read More
Video - Energy Saving Tip 6. Image is a photograph taken from the inside of a home looking out a window over the lawn and street.

Video – Energy Saving Tip 6

April 19, 2023
Cool your home by opening the windows at night and save on your energy bill. The outdoor breeze will keep your home feeling cool. Read More