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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.

Air Conditioner Repair in Waukesha, 53189

“Service date 6-24-2022. Service Technician Eric Osterman.
Very pleased with my technician's knowledge, professionalism, politeness and attention to detail concerning the repair of my Carrier AC unit. I am also very appreciative of the time Eric spent explaining the new Carrier line of AC units to me and the model that will most meet my family's budget and needs. See you in Autumn for my Carrier furnace tune-up.”
- Kevin W.

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
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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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What Does Indoor Air Quality Have to Do With Allergies? Image shows woman's hand above dusty table with dust on pointer finger.

What Does Indoor Air Quality Have to Do With Allergies?

October 15, 2022
Did you know the average American spends nearly 90 percent of life indoors? That’s why it is increasingly important to ensure indoor air quality (IAQ) is clean and healthy. If your Sussex home is facing air-quality issues, you may be suffering anything from minor discomfort to significant allergy or health problems. Our team at Interstate… Read More
Image of someone. Video - Why does my heat pump smell like it's burning?

Video – Why Does My Heat Pump Smell Like It’s Burning?

September 30, 2022
You turn on your heat pump, and you smell something burning. What should you do? Who should you call first, the fire department or your HVAC technician? First assess what the smell most likely is, and you may not need to call anyone. Of course, if you’re still nervous because you just don’t know, turn off your heat pump and give one of our highly trained technicians a call to come out to diagnose the smell for you. Read More
Air conditioner with maintenance tools and service reminder in residential back yard. Is HVAC Preventative Maintenance Worth It?

Is HVAC Preventative Maintenance Worth It?

September 15, 2022
Want to know the best way to stop problems with your heating, ventilation, and air conditioning (HVAC) system before they start? Create a preventative maintenance plan. Read More