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Maryland’s Best HVAC Contractor

If you’re looking for the best HVAC contractor in Maryland, call GAC Services! We install, repair, and service any and all HVAC systems in Montgomery County and Frederick County.

What makes us the best? We were recognized as the 2015 ACCA Contractor Residential Contractor of the Year—making us your go-to contractors for HVAC service in Maryland. Thanks to our skilled team of heating and cooling technicians and you, the customers we work so hard to provide outstanding customer service for, we can proudly say we are the best HVAC contractor in the Old Line State!

What Makes Us the Best?

Over the years, even back when you might have known us as Gaithersburg Air Conditioning & Heating, GAC has focused on putting the customer first. We strive to provide outstanding customer service throughout every sales call, install, repair, or service appointment.

We also pride ourselves on providing up-front pricing, so you’ll never worry about any hidden fees when your job is complete. You’ll know exactly how much our service will cost before we begin any work! Not satisfied with our work? Our 100 percent customer satisfaction guarantee means we’ll come back and fix your system, free of charge. This is all part of our mantra and what makes us the best HVAC contractor in Maryland—the GAC Difference.

The GAC Difference

“What do our customers want?” That’s the question that’s been driving the way we do business at GAC from the very beginning—back when you might have known us as Gaithersburg Air Conditioning & Heating!

While our name may have changed, the way we do business hasn’t.


These are just a few reasons why your neighbors love working with GAC. It is this commitment to excellence, along with our friendly and honest professionals that has helped us satisfy tens of thousands of customers throughout Maryland over the years. And it is this that we consider the GAC difference.

Contact us for a free estimate on a new heating or cooling system or to schedule service today.

We’re looking forward to serving you and hopefully making you a customer for life!

Best Heating & Cooling Contractor in Maryland

When you’re in desperate need of an HVAC contractor, you can count on GAC. We provide comprehensive heating and cooling services throughout Maryland, no matter what kind of system you have. We service:

Most Nationally Awarded Bryant® Dealer in the U.S.


Bryant, a leading manufacturer in the HVAC industry, awarded us the 2013 Bryant Dealer of the Year—making us the best installer of Bryant heating and cooling systems in Maryland. While we know this is in the past, we still strive to be one of the best HVAC contractors working with Bryant year-after-year.

We are the most nationally awarded Bryant dealer in the U.S. In addition to being named the 2013 Bryant Dealer of the Year, we’ve received the Bryant Medal of Excellence (MOE) award eight times! So, if you wish to install a Bryant HVAC system or need a contractor to service your Bryant equipment, give us a call!

Schedule Service from Maryland’s Best HVAC Contractor

Ready to get started? To schedule service, contact us online or give us a call. We offer free estimates!

Financing Options Available

At GAC, we understand how important a functioning HVAC system is for your home. This is why we offer flexible financing options to help you take care of your new HVAC purchase, so you can get back to taking care of what matters most to you.

Priority Maintenance

A well-maintained HVAC system can save you from having to invest in costly repairs down the road. Learn more about the priority maintenance services offered by GAC Services.