Aerial view of a church surrounded by fall foliage.

Thank You for Visiting Sussex's Top Residential and Commercial Heating and Air Conditioning Company

Reach Out Today to Get Help!

Autumn colored forrest at the edge of a lake.

Thank You for Visiting Sussex's Top Residential and Commercial Heating and Air Conditioning Company

Reach Out Today to Get Help!

geese flying at sunset.

Thank You for Visiting Sussex's Top Residential and Commercial Heating and Air Conditioning Company

Reach Out Today to Get Help!

Virtual Consultations Are Now Available!

Headline-Our-Services

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.

building
dad-daughter
duct-pattern
carrier-product
carrier-fad-logo

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.

Headline-Read-Our-Reviews

We love hearing from our customers! If you’ve had us work on your HVAC system we would love to hear from you too.

Gas Furnace Maintenance in New Berlin, 53146

“Nice friendly tech did a good job and explained what he did.”
- Shane F.

Gas Furnace Maintenance in Waukesha, 53189-9215

“Eric was here for our usual fall Gas Furnace Maintenance inspection and answered many of our questions regarding our filters and the air quality in our home. Since we keep the furnace fan on continuously, there were questions about the Aprilaire control board. Some hints as to what number setting to use during the change of seasons in Wisconsin. He also offered information about our Air Quality and what we could do to take care of this situation. He was very professional, and we were very pleased with the exceptional service he provided.”
- Patricia S.

Air Conditioner Maintenance in Brookfield, 53005

“The Interstate appointment was made promptly. The technician arrived on time and was very efficient in inspecting our furnace and air conditioner. We are very satisfied with the service performed.”
- Kathleen M.
duct-mark

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.

Headline-Read-The-Interstate-Blog
5 Tips to Improve Your Indoor Air Quality This Fall - Lady Wrapped up in a Blanket.

5 Tips to Improve Your Indoor Air Quality This Fall

October 4, 2023
Get ready for cooler weather here in Sussex—fall is here! Read More
Video - How Can I Make My Home More Comfortable? Animation of woman laying in bed warm.

Video – How Can I Make My Home More Comfortable?

September 27, 2023
Is your home always uncomfortable either upstairs and down? You should consider zoning your home! Read More
Schedule Your Annual Furnace Inspection Now - Handsome African American construction foreman or building contractor stands in front of home that is being built for charity. Volunteers are working on the home in the background. He hsi wearing a hard hat, safety glasses and volunteer t-shirt.

Schedule Your Annual Furnace Inspection Now

September 6, 2023
What’s at the top of your fall to-do list? Make sure it is your furnace.  Read More