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Cool Breeze Plumbing
- Responsive
- Warranty
- Work
“Cool Breeze kept it running for years and when it finally did die they had the entire system replaced with a new, more energy efficient system in less than 48 hours.”
Best HVAC Contractors in Gaithersburg, MD
24 companies listed · all 24 in Gaithersburg · 5 open 24/7 · 13 open weekends · 18 rated 4.5+
Data verified October 18, 2026
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Michael Bonsby Hvac
- Plumber
- Basement
- Options
“Installation or replacement of HVAC system is almost a once in a life time project and when it has to be done some time in your life you need a company that understands your doubts, nervousness and then cares, openly explains, and addresses all your ...”
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Presidential Heating & Air Conditioning
- Heat Pump
- Work
- Humidifier
“We are fairly new customers but so far we have been very pleased with the customer support and expert technicians who are servicing the aging HVAC in our three-level townhome.”
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ADI Heating & Air Conditioning
- Estimate
- Questions
- Competitive
“He also gave us some valuable additional recommendations for how to improve our heating and cooling systems, including some structural changes to our home that will make a difference.”
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Parker Pearce Service Experts
- Plumbing
- Electrical Work
- Dryer Vent
“Aaron May, the technician, was very professional, well trained for the task he had to perform, and communicated his findings while performing the HVAC maintenance task.”
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James A. Wheat & Sons
- Gas Fireplace
- Faucet
- Garbage Disposal
“Technician John White Jr did a great job of quickly diagnosing and fixing the issue with my AC unit (loose control board wire), starting with the simplest, most upstream possible causes and working downstream step by step.”
The 24 companies listed for Gaithersburg, MD work on furnaces, heat pumps and air conditioners. Each profile repeats what the company publishes about its hours, its license and the equipment it fits, alongside ratings and quotes drawn from public reviews.
Area overview: Gaithersburg, MD
All 24 companies we list here are in Gaithersburg itself. We have 26 companies in Gaithersburg on file; this page shows the highest-rated 24. 22 of the companies on this page have a rating, from 4.2 to 5.0 across 11,478 reviews; 12 have 50 or more reviews and 18 are rated 4.5 or higher. When customers rate these companies on specific qualities, they most often praise professionalism (84%), quality (82%) and responsiveness (81%). The topics that come up most in reviews of the companies on this page are "price", "efficient" and "estimates". 5 are open around the clock; 13 are open on Saturdays and 10 on Sundays. The services the companies on this page list most often on their websites are heating (4), indoor air quality (3), plumbing (3), water heaters (3) and air conditioning (2). 11 show a license on their websites; 1 lists staff certifications (LEED) and 7 have a BBB rating of A or A+. 20 have ten or more years of experience, the longest 76 years. 10 offer emergency call-outs; 7 offer financing or payment plans; 10 give free estimates; 8 are family- or locally-owned and 12 list coupons or special offers. We count these figures across the companies on this page; hours and prices change, so confirm the details with the company before you book.
Which companies listed for Gaithersburg answer no-heat calls at night?
Round the clock availability appears in 5 of the 24 listings on this page. An overnight visit is usually a diagnosis and a temporary fix, since supply counters are shut until morning. Ask what the after hours call out is before the truck leaves.
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Atlantic Coastal Cooling & Heating
- Furnace
- Fair
- Service Plan
“Not only were they the most competitive in terms of pricing (controlling for equipment and thoroughness of their proposal), Jamie's no-pressure sales approach was much appreciated.”
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Pipeworks Plumbing
- Call
- Gas
- Inspection
“He explained everything that needed to be done (replaced seal in toilet and replaced shutoff valve), provided an estimate, and performed the work without issue.”
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GAC Services
- Electrical Work
- Outlet
- Generac
“Good Service with professional skill, Jasser is very friendly and explained to us all details how HVAC works, what are do and don't that the owner wants his system effectively working for cooling and heating.”
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Sichinava Heating and Air Conditioning Inc.
- The Future
- Heat Pump
- Error Code
“Showed up to my house on time and showed me how to read the error codes on the furnace and how to keep it running when mine shut down during the coldest day of the winter season....”
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Congressional Heating & Air Conditioning
- Price
- Efficient
- Job
“Kevin accurately saw the problem and proposed solutions (increasing length of piping, moving the unit to the side of the house, introducing 90* bends, replacing and rehanging the line set inside the house, and putting vibration absorption pads under ...”
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United Service Specialists Heating
- Questions
- Information
- Diagnosed
“We've had plumbers come out as well, Justin & Chris most recently to help us with a leaky kitchen faucet which turned out to be a whole home water pressure issue.”
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Simply Home Service
- Heat Pump
- Expertise
- Condo
“Project required multiple trips in/through the house (removing old equipment and installing new), and Sean and his workman left my home in immaculate condition.”
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Mallick Plumbing & Heating
- Estimate
- Hose
- Pressure Valve
“Gave us a camera view of our cast iron pipe to the city hookup, cleared a blockage somewhere between our washer and outside drain, and cleared out the drain in our upstairs bathroom sink.”
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Harvey W Hottel
“They only with with commercial companies, but the person who answered the phone was very helpful and friendly and directed me to Mallick Plumber who were fantastic.”
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Germantown Heating & Air Conditioning
- Unit
- Questions
- Home
“When I happened to mention that the hose had got stuck to the bib over the winter, he offered to take it off for me, thereby saving me a lot of work (I was ready to get a hacksaw from my local hardware store to saw it off).”
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Alihan LLC
- Future
- Bathroom
- Dryer
“Alihan LLC came out and gave me a great estimate, and although I was not ready to complete the job right away, they didn't pester me which I appreciate it.”
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Air Quality Heating & Air Conditioning
“He listened carefully to my HVAC/heating system concerns and then examined the system and diagnosed the problems.”
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Stang Plumbing & Heating
- Work
- Basement
- Job
“My interior main sewer line needed replacement, and the entire process went smooth as silk with absolutely outstanding communication, planning and coordination not only with me, but with my tenants as well.”
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America's Green Heating & AC Co.
- Warranty
“We had to replace replace our whole AC unit, basically all the internal work that had to be done was done.”
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Air Conditioning & Refrigeration
“Very thorough and very reasonably priced”
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Santy and Sons Hvac
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Densel Hvac Co
“For any heating cooling commercial and residential call these guys superior service and never made me feel like just a "number".”
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Enviro-Aire Mechanical Services
Why these companies made our list
What customers say about companies in Gaithersburg
- “Dennis let me know he was coming to fix the furnace, brought the parts, dealt with everything in a timely fashion and walked me through what he had done.” — customer of United Service Specialists Heating
- “Great customer service and workmanship. I needed a new air conditioner and furnace and got it installed in less than a week.” — customer of ADI Heating & Air Conditioning
- “Sean was helpful and knowledgeable. Work was completed on schedule and they left the work area clean.” — customer of Simply Home Service
- “We had our gas furnace replaced yesterday. The company was on time, organized, polite and efficient.” — customer of Congressional Heating & Air Conditioning
- “They took the time to lay down tarps and left my laundry room (where the furnace is) cleaner than when they got there.” — customer of Congressional Heating & Air Conditioning
Excerpts from public reviews of the companies listed on this page.
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