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-Servicing Northeast Ohio-

Family-Owned Geothermal, Heat Pump & Furnace Repair & Installation

We install and service heat pumps, geothermal, and traditional heating and air conditioning systems in Northeast Ohio. We're family-owned and operated and have been in business since 1992, with excellent reviews. DMiller Mechanical will meet all of your HVAC needs.

Our Services

If you want to stay warm in the winter and cool in the summer and save some money on your utility bills you're in the right place! We love making homes comfortable and comfort systems more efficient.

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  • Air Conditioning Installation

    Get a quality air conditioning system and enjoy a cool house for many years. We'll size your AC unit correctly and install it professionally.

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  • Furnace Installation

    Need a new furnace? We can recommend the perfect one for you and install it quickly and professionally.

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  • Geothermal Installation

    Use the ground around your house to heat and cool it year-round! Geothermal is a super-efficient way to keep your home comfy.

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  • Heat Pump Installation

    Heat Pumps can pull heat from the air to keep you warm in the winter and double as an air conditioner in the summer while saving you money.

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  • Heat Pump Repair

    When your Heat Pump System needs expert repairs or maintenance, call us for expert repair and maintenance! With years of experience, we've got you covered. Request a quote today!

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  • Geothermal Repair

    Geothermal systems are generally pretty low-maintenance but sometimes they need repairs. That is when you need a professional! Give us a call and we will get your system running smoothly.

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  • Keeping Our Customers Comfortable & Happy

    See what our customers have to say about us...
    Over the years we've had the privilege to serve customers from Stark, Columbiana, Carroll, Mahoning, Tuscarawas, and all surrounding Ohio counties. We appreciate all the friends we've made and the referrals we've received from our happy clients.

    Check out our Google and Home Advisor reviews and leave us your own if you've enjoyed working with us.

    D. Miller Mechanical, LLC IconD. Miller Mechanical, LLC

    25299 Sandy Spring Rd, Minerva

    5.0 22 reviews

    • Alan Phillips’s Avatar Alan Phillips ★★★★★ a year ago
      We have been lucky enough to have D. Miller Mechanical do two separate installs for us. On both, they have been very knowledgeable, professional, courteous, and receptive through the whole … More process. I highly recommend if you’re in the market to give them a call and find out yourselves!
    • Michael Bentfeld’s Avatar Michael Bentfeld ★★★★★ 5 years ago
    • T&J *’s Avatar T&J * ★★★★★ 2 years ago
      Dwight's two sons came and removed our old heat pump and replaced it with a brand new Bosch brand heat pump. They were very friendly, knowledgeable and answered all my questions! Their … More work was excellent and when they left, here was not a single thing left, everything was clean and the workmanship was perfect. We were very pleased with it and it works so much better than the old one and is much more efficient. I highly recommend Dwight Miller for anything you have to have done of air conditioning and heating issues. Ted Steckley
    • Scot Rourke’s Avatar Scot Rourke ★★★★★ 5 years ago
      Dwight and his team have bailed us out more than once. First, he was the most responsive in an emergency call, and did amazing work for us. Then he later replaced the whole heating and … More cooling system, plus installed a wireless smart thermostat, and did amazing work. He communicates well, overdelivers, is prompt, does great quality work, really cares about the ultimate outcomes, and is just a pleasure to work with. We will keep using him for all our needs.

    A Trustworthy HVAC Company Built by a Family

    A great reputation

    Proverbs 22:1 says "A good name is more desirable than great riches." That's so true and it's how we run our business here in Northeast Ohio.

    In business since 1992

    We've been working hard and keeping customers comfortable since before most people had internet. A lot has changed in the world since then and our family has grown up a lot but we still run our business the same way.

    Quality equipment - Expert installers

    We don't play the price game because that means selling inferior equipment. We work with equipment we know will last because we've seen it last. Brands like Bosch, Carrier, and Bryant.

    New Air Conditioning Unit Photo
    New Heat Pump Unit Installation Photo
    New Furnace Duct Installation Photo
    Miller Family Photo

    Frequently asked questions

    Here are some questions we get asked pretty often so let's go ahead and answer them. If you still have questions, please contact us.

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    The federal tax credits for home heating and cooling equipment ended for systems installed after December 31, 2025. That includes the 30% Residential Clean Energy Credit for geothermal heat pumps and the Energy Efficient Home Improvement Credit of up to $2,000 for air-source heat pumps and up to $600 for qualifying furnaces and central air conditioners.

    If your system was installed in 2025 or earlier, you may still be able to claim the credit on that year’s tax return. Your tax professional can tell you for sure.

    Some utilities and equipment manufacturers still offer rebates or seasonal promotions from time to time. When we quote your project, we’ll tell you about any that apply, and we’ll help you compare long-term operating costs so you can see what a high-efficiency system really saves.

    We install and service in Stark, Columbiana, Carroll, Mahoning, Portage, Tuscarawas, and all surrounding counties in Ohio.

    Absolutely! Heat pump systems are much more efficient than they used to be and are extremely efficient even in cold weather. You will still need a backup heat source for an air-source heat pump system but most of the time you won’t need to use it.

    A geothermal system harnesses the heat trapped underground to heat your house. By laying a series of pipes several feet below the surface of your yard, we can use the difference between the ground temperature and air temperature to keep your house warm in the winter and cool in the summer while saving you money!