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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.

Professional HVAC Install

Magic! Our problem was resolved in about four days. Thanks again for the recommendation and the professional install. -Cheryl  

Furnace and Air Conditioner Installation

I just wanted to drop you a quick note to say thanks for all of your efforts in getting us our new furnace and air conditioner—the installation crew did a fantastic job. I’ve shown a few people the installation and they were amazed at the neat, professional job that was done. Plus, the whole crew was very friendly and patient with me and my endless questions. The system is working beautifully. As you suspected, the temperature difference between the upstairs and downstairs has almost completely disappeared, and everything is so quiet you can hardly tell it’s on. I’m almost excited to get my next electric bill to see how much money we’ll save. We literally could not be happier with the system. I’m sure there are more exciting home improvements, but this necessity has given us the most benefit and a lot of enjoyment. I will highly recommend you and Interstate to anyone who’s in the market for new HVAC equipment, starting with my dad, who has a furnace and air conditioner that are nearly 20 years old. Thanks again. -Pete

Furnace and Air Conditioning System Installation

Your company recently installed a new Carrier® furnace and air conditioning system in our home. We were very pleased with the quality of service we received. From David, who oversaw the project, to the entire team helping with this installation, we were most impressed. Everyone was professional, knowledgeable, and extremely courteous, and did an excellent clean-up job when done. The entire job was completed in one day. This is one of the most satisfactory contractor experiences we have had. We will not hesitate to recommend Interstate Heating whenever the occasion arises. -Phillip R.
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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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lower your winter heating bill

5 Ways to Lower Your Winter Heating Bill

January 27, 2022
When the temperature gets low, your energy bill gets high. That’s because you spend more time indoors during the winter. And we don’t blame you—it can get pretty cold here in Wisconsin. Read More
Video - Should I Set My Thermostat to ON or AUTO?

Video – Should I Set My Thermostat to ON or AUTO?

December 31, 2021
On most thermostats, you can choose between On or Auto for your fan setting. Read More
happy new year

Happy New Year

December 31, 2021
Happy new year from Interstate Heating Co.! Read More
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