ONE HOUR Heating & Air Conditioning

One Hour Heating and Air Conditioning



(571) 421-1888

HVAC Repair & Replacement Northern VA

Your Comfort is Our Priority! Call Us for All Your Heating & Air Conditioning Needs.

One Hour Heating & Air Conditioning Services

HVAC Diagnosis & Service

Diagnosis & Service

HVAC Repair & Replacement

HVAC Repair & Replacement

Indoor Air Quality

Indoor Air Quality


Why Choose One Hour Heating & Air Conditioning?

One Hour Heating & Air Conditioning is dedicated to providing the best value and customer service in the Northern Virginia area. To us, One Hour isn’t just our name; it’s a promise. We respect and understand the value of our customers’ time, so we guarantee our technicians will arrive on time to address your heating and air conditioning needs. We stand by our workmanship and our products because your family’s comfort is our top priority. We strive for professionalism in every customer interaction and we always put safety first. In addition, our company works hard to be responsible and active members of our community. We invite you to learn more about our services and to experience the One Hour difference.

What Our Customers Are Saying

Modern Mechanical has been doing my HVAC service for a couple of years now. Both times I’ve had service/cleaning, the technician seemed very knowledgeable and had a clean, professional appearance. Their prices are fair and their response time to my service request was well above adequate. The technician finished the service and then promptly cleaned up any mess that they had made. I normally do all house maintenance stuff on my own, but HVAC is a category that I have no experience in. Modern Mechanical has made this part owning a home very stress free. I would definitely recommend them.

Nathan J.

It is not often you receive tremendous customer service anymore. Modern Mechanical delivers on customer service in spades. Their equipment is first rate, prices are extremely competitive and their service is top notch. No reason to look elsewhere.


Washington, D.C.

They reset my thermostat. My house was really very cold and I could not figure out what the problem was. I gave the guys over at One Hour Heating & Air Conditioning operated by Modern Mechanical a call and they were able to come and assess the problem. They were quickly able to determine that my thermostat needed to be reset. After taking care of that they made sure everything was ok and then they left. My house is much warmer now and it is all thanks to these guys. I would definitely recommend them to anyone.

Veraline J.


Modern Mechanical Installed A Trane Dual Fuel Unit Christmas week 2014. Did A GREAT JOB, Also Zoned My Two Story Home And Now It Is Very Comfortable Up & Downstairs. Very Reasonable Pricing & Did It In 1 Day, Wow. I Do Highly Suggest If You Need Heating & Air Help, Give These Guys A Call.

Rick G.

Brett, Paul, and Bobby installed my new first level A/C unit and furnace today. This is the third time I’ve asked Modern Mechanical to upgrade my existing equipment, and once again I was highly satisfied with the effort. All three of my installation team (Brett, Paul, Bobby) were consummate professionals, deftly completing the work ahead of schedule, briefing me on the changes, answering my questions, and leaving me as a very satisfied customer. I will happily promote Modern Mechanical and their fine crews to my friends and neighbors and when I need my next upgrade I will call upon them once again without hesitation. My hearty thanks to Brett, Paul, and Bobby; and also to Modern Mechanical. Great work!

Dave C.

We recently were recommended by a friend to use Modern Mechanical to replace our outdated a/c system. From the phone call setting up the appointment to the salesman who came to give us a quote to the install, we were more than impressed with the professionalism of this company and their employees. We need to replace the other a/c unit and without hesitation, we will be calling Modern Mechanical. They are reliable, professional, informative and punctual.

Danielle W.

Modern Mechanical replaced our 20+ year old HVAC system and hot water heater. The job was not an easy one given the complications of getting the condensate lines from the furnace to the outside compressor, but Modern Mechanical stayed late each day during the installation to make sure it was done right.

They were very honest about recommending the right system for the house and balancing upfront cost with energy savings, maintenance, reliability, etc. In the end we went with a Lennox XP25 with a dual fuel SLP98V furnace. We’ve had the system for 4 months now and it is running beautifully, with significant energy savings.

We were really impressed with Modern Mechanical from the initial visit and quoting process all the way through the end of the installation. We would definitely use them again and would highly recommend.

Andrew N.

Falls Church

I have got to say that I was (and still am) very impressed with their customer service, their professionalism, attention to detail and willingness to “make it right.” I searched and searched for the perfect HVAC company and I think I have found it. Modern Mechanical is superb. I just bought a brand new AC unit and I am very pleased with this company. I highly recommend them to anyone in the Triangle. And if you do purchase an AC unit from them, you can get the Duke Energy rebate (not all HVAC companies do).

Suzanne V.

Paul and Travis came out to install our new HVAC units and heat pump. They are awesome guys! Great to work with and very professional. The new units are fantastic and they took the time to go over everything with me. They really made it all look professional and tidy, going the extra mile to move pipes and stuff they didn’t have to so it would fit better. I recommend Modern Mechanical to everyone and I will request Paul and Travis next time I need something installed.

Adam R.

Fairfax Station