Hours: 24 Hour Answering Service

MD (301) 260-6000 VA (703) 777-9211

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Mannix Heating & Cooling was founded by Jerry Mannix in 2010.

At the time, Jerry had worked for one of the largest heating and cooling companies in the country. During the many years with this company, Jerry watched this company grow from a large local company to a massive nationwide consortium that grew mainly by acquiring smaller companies. He also witnessed the company change from a service oriented company that cared for it’s customers, to a large conglomerate that was owned by a private equity firm who cared more about the bottom line than the customer. Their motto was “we are a sales and marketing company that just happens to sell HVAC equipment”.

Jerry felt that during this change, the company had lost its way. Jerry felt strongly that taking care of the customer should come first and the bottom line came second. His idea that he could do it better was the driving force behind why Mannix Heating & Cooling was started. He wanted to build a company that cares for their customers, gives them an honest assessment of the problem with all the possible solutions at a fair price.

Jerry has over 30 years’ experience in residential HVAC and holds master licenses in HVAC, gas fitting and plumbing. He leads a team of customer focused employees who all subscribe to the same motto “Take care of the customer first”, everything else comes second. In its short time, Mannix Heating & Cooling has grown to over 25 employees with 19 trucks to serve you. They have an outstanding reputation for customer service and have some of the most experienced techs in the industry. Just look them up on Angie’s List or read what others are saying about them on Google or Yelp.

If a problem occurs with your heating or cooling system, don’t panic, call Mannix!


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Customer Reviews

Shondra J ones

They were lifesavers!!! My furnace went out and after three days of dealing with the home warranty company and the unscrupulous vendor they sent to my home, I called Mannix. The service technician was friendly, efficient but most of all honest. He found the problem after twenty minutes, saving me thousands in unnecessary replacement costs. It is refreshing to know that honest people still exist.

Lynne Wilson

I contacted Mannix from a referral of a friend who has benefitted from the excellent service this company provides. I found out a couple I know in Vienna had their heat pump stop working a few months ago and needed to be replaced. I called up the Mannix office later in the day on Monday 11/30/20 and provided information needed. I had a proposal in my email the next morning 12-01-20. This will enable me to discuss with my friends how they wish to proceed with fair financing options available too. This is EXCELLENT customer service and I would like Mr. Mannix to know that Sarah is an amazing professional face for his company. I plan to become a customer of theirs by signing up for the annual maintenance plan which is very reasonable priced. Sincerely, Lynne Wilson

Philip Slingerland

Been a happy Mannix customer for a few years now, but recently had them replace our aging HVAC system. The whole process was very painless, from Eric helping us decide which system was right for our home, to the efficient and professional installation by Billy and Matt. I am very pleased with the new system and very impressed with the level of service, communication, and detailed information I received from everyone involved. Highly recommend!


Before dealing with Mannix I used two very well-known and “reputable” HVAC companies who did nothing but rip us off over the years. I was frustrated and found Mannix Heating & Cooling about 10 years ago. They installed a new HVAC system in my old home, and installed a water heater and various other items in my new home. They also have been doing yearly maintenance for years. Their employees are the most honest, reliable, and knowledgeable individuals in this industry. We recently had an issue with our HVAC system and they came out within a few hours on an emergency call. The technician was prompt, kind, professional, and very fair. He figured out what was wrong with our system quickly and remedied it immediately. Do not hesitate to call them if you need anything–you won’t regret it!

Wendy Collins

Mannix has always been professional from service calls to repairs and replacements. The technicians are always polite and knowledgeable. They consistently exceed our expectations.

Gary Hendricks

Mannix proved very responsive in fixing my A/C system. The tech, Erick, was very professional by taking the time showing and explaining to me the system problem prior to taking action replacing the coil. Ashleigh, customer service, was excellent in addressing and following through on concerns in order to achieve total customer satisfaction.

M. Reyzer

My 24-year-old heat pump finally decided to stop working. I sent a request for a replacement estimate late one night through the Mannix website and received a phone call early the very next morning to set up an appointment. Eric Holzworth stopped by my house the next day to go over my options. He was wonderful and so easy to work with and answered every question I had. He definitely listened to me and my concerns did not push me into purchasing a high-end system which I didn’t need. The technicians arrived at 8am and were finished with the entire installation by 1pm. They were very courteous and left my house in pristine condition. I HIGHLY recommend Mannix! They always returned my calls and emails right away, and Eric made sure I received all of my equipment on time–even with Carrier factory delays/limited supplies due to COVID. So glad I chose Mannix. I love my brand new Carrier system and my cold house during these hot and humid days.


We were in desperate need of a fix on our AC system during the July heatwave. The issue arose on a Saturday. Mannix came to the rescue in short order, fixed it, and at a reasonable price.

Silvio G was the technician, and he was GREAT.

We would definitely use Mannix again!

Patricia Ryan

I have been using Mannix for years. They have replaced my HVAC system and I have them do maintenance twice a year. The past couple of visits have been done by Ramiro. He is professional, polite, knowledgeable, and very helpful in assisting me with tips on the best ways to operate my system. Today, he installed a water safety device and taught me exactly how it works and how to reset it. I’m so impressed with him! I will continue with Mannix for years to come as I find them to be very reputable and reliable. Thank you!

Rachel Craft

I’ve been using Mannix for years and have never been disappointed. They’ve replaced my HVAC, hot water heater and installed a humidifier on my furnace. Whenever I need them, they can get me on the schedule in a timely manner. All the personnel are great and I trust Jerry and his team with their recommendations and the work they do. Would highly recommend.

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