About Great Lakes Heating & Cooling, LLC

Great Lakes Heating & Cooling, LLC received great reviews. They provided a great price and outbid 4 other competitors. They installed a Comfortmaker 3ton 14 seer. The quote was approved via email, the unit was ordered, and it was installed in 3 days. The team is very responsive, knowledgeable, professional, and trustworthy. They installed a home HVAC system and a garage heater. Doug was absolutely wonderful to work with. He called back right away on a Friday night. He took the time to walk through getting the furnace functional for the night. He was honest, helpful, and never pushy. His team came out the very next day and installed the new furnace. They went above and beyond. They installed a new AC and a new ecobee thermostat. When there was a warning message and small water leaking, they got to the house within the hour and fixed the issue, working until after 6pm. They were very courteous and friendly. During hot weather, Doug came out the next morning to check an 18 year old condenser. After a thorough cleaning and check, it was up and running. When an earwig got into the contactor, Doug fixed it in no time and the price was very reasonable. Highly recommended.

Reviews for Great Lakes Heating & Cooling, LLC

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  • Mar 2026

    Doug at Great Lakes Heating & Cooling, LLC was absolutely wonderful to work with. We were referred to him by our electrician after a power outage caused our thermostat to stop working due to a furnace issue. Even though it was Friday night around 8:00 PM, Doug called us back right away after we left a voicemail.

    He took the time to walk my husband through getting the furnace functional for the night, even though we had never worked with him before. That alone says so much about the kind of person he is.

    Doug came out the following week, was incredibly kind, and thoroughly explained that we would need a new furnace. He was honest, helpful, and never pushy....read full review

  • Jun 2025

    These folks are absolutely awesome. They installed our new AC last fall and a new ecobee thermostat and it’s been awesome. We had a warning message on the eco thermostat and I’d see some small water leaking from the furnace which was connected to the warning. I called them this afternoon and they got to the house within the hour and diagnosed and fixed the issue, working until after 6pm. Very courteous and friendly and patient about answering questions as my wife and I like to learn about the systems. Can’t give them enough praise. 5 stars isn’t enough! Thank you Doug and Tyler!

  • Aug 2024

    5/5 During the recent hot weather our central air unit began having issues on the weekend. I contacted Doug and he came out the next morning to check things out on my 18 year old condenser. After a thorough cleaning, electrical and refrigerant check we were up and running.
    If you have any HVAC issues, I highly recommend Great Lakes Heating and Cooling.

Hours

Monday: Open 24 hoursTuesday: Open 24 hoursWednesday: Open 24 hoursThursday: Open 24 hoursFriday: Open 24 hoursSaturday: Open 24 hoursSunday: Closed

Location

N7837 Division St, Oconomowoc

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