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Gaithersburg, MD
Gaithersburg, MD
Bringing Comfort Home
Gaithersburg HVAC Services
One Hour Air Conditioning & Heating® of Gaithersburg
4.8
Heating, AC & Furnace Repairs in Gaithersburg, MD
When homeowners want a reliable heating or air conditioning system that they don’t have to think about, they call One Hour Heating & Air Conditioning. We are the premier HVAC service provider in the United States for a simple reason: we actually care about your comfort.
At One Hour, we respect you, we respect your time, and, most importantly, we respect the trust that you put in us to keep your home comfortable. It’s why we back all of our work with a 100% customer satisfaction guarantee for two years, and it’s why we’re always on time—guaranteed.
We Have a Reputation
For Being Punctual, Friendly and Knowledgeable
4.8
Diane Moynihan Stefan
03-26-2026
“Mr Gilmer was very patient explanation all the work ahead of time. Very good experience today@”
Cheryl Poole
03-26-2026
“Mr Gilmer did a fantastic job today repairing my furnace.”
Leah Henry
03-25-2026
“Gilmer and Ivory were nice and welcoming! Professional and they broke down every concern about my HVAC system.”
Nadia Kendall
03-25-2026
“I have been with One Hour for over a decade. Mr. Gilmer has worked on my HVAC system a few times now and each time he isn't satisfied with his work until everything is in peak working condition. He takes his time to explain what he's doing and he does so with pride. We are thankful for Mr. Gilmer's work and dedication to your products working in our home.”
michele murphy
03-24-2026
“Mr Gilmer was professional and explained everything to me (repairs, problems, etc)”
Wayne Simms
03-20-2026
“Mr Gilmer”
Jackie Hilton
03-19-2026
“Mr Gilmer was prompt, courteous, and knowledgable. He took time to explain his review and recommendations.”
Dean Wiles
03-18-2026
“Mr. Gilmer and William did a great job checking my HVAC and answering my questions.”
Hirad Yaldaei
03-18-2026
“Had a great experience with Mr Gilmer! Highly recommend!”
Anna Kilduff
03-17-2026
“Mr Gilmer”
Our customers love what we do because we treat them like the neighbors they are to us. While we carry the One Hour name, we’re an independently owned and operated business with a personal investment in the local community. We back our work with a 100% satisfaction guarantee, provide StraightForward® pricing guides for your benefit, and will pay you back for being even one minute late to an appointment.
Here For You
When You Need Us Most!
'Round the Clock Availability
No matter the hour, you can trust One Hour to be there to help you when you get hit with the unexpected.
100% Satisfaction Guarantee
We guarantee our materials, labor, and craftsmanship for up to two years from the date of your service.
StraightForward Pricing® Guide
Before we start any work, we discuss your available options so you know exactly what you are getting and how much it will cost. No hidden fees!
Always On Time…Or You Don’t Pay A Dime!®
We understand your time is valuable, so we promise to arrive at your home within the predetermined time window that you select, or your service call is free.
Financing Available!
Prioritize your comfort without fronting the entire bill on day 1 – contact us today to learn more about financing options.
Hours of Operation
We are available 24/7 to take your call for emergencies. For all other services, our appointment hours are:
Monday
24 hours
Tuesday
24 hours
Wednesday
24 hours
Thursday
24 hours
Friday
24 hours
Saturday
24 hours
Sunday
24 hours
Authority Brands is the leading provider of in-home services, building brands that support the success of franchisees as well as better the lives of the homeowners we serve and the people we employ.
