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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.

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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V-MSC_002-HVAC-Maintenance

Video – Do I Need to Schedule a Maintenance Appointment?

September 30, 2021
for your business. Catching symptoms of trouble early on can keep your units working efficiently and safely as long as possible. Read More
fall hvac maintenance

Fall HVAC Maintenance

August 31, 2021
As the saying goes, “Time and tide wait for no one.” Whether you’re prepared or not, the summer months and warmer weather are going, moving aside for fall and cooler temps. That means here in Mequon you need to think about preparing your heating, ventilation, and air conditioning (HVAC) system for fall maintenance. Read More
improve your home's indoor air quality

Improve Your Home’s Indoor Air Quality

August 2, 2021
Improving the indoor air quality (IAQ) at your Germantown home or business makes sense on so many levels. Consider your health, your comfort, and your household budget. It’s hard to imagine a more important investment than improving the air you breathe! Read More