What does the One Hour mean in your company name?

The 'One Hour' in our company name indicates our guarantee to be at your home in the predetermined window quoted when you set your appointment. If we do not show up within that window, your service call fee is waived. 1. Express Appointment: This is an appointment that is scheduled during a specified one-hour time slot. You are promised that a technician will arrive at your home within this one-hour time window. You will also receive a call when the technician is en route to your home. 2. Reserved Appointment: This is an appointment that is scheduled during a specified, two-hour time slot. You are promised that a technician will arrive at your home within this two-hour time window. You will also receive a call when the technician is en route to your home. 3. Standard Appointment: This is an appointment that is scheduled during a specified four-hour time slot. You are promised that a technician will arrive at your home within this four-hour time window. You will also receive a call when the technician is en route to your home. 4. Stand-By Appointment: This appointment is for overflow situations. This appointment will not have a specified time. You will receive a call when the technician is en route to your home. 5. Emergency Appointment: This appointment is for an unspecified time after normal business hours Monday – Saturday and all day on Sundays/Holidays. Calls are dispatched in the same order they are received. You will also receive a call when the technician is en route to your home.

Do you service emergencies after-hours?

Yes, we offer emergency services 24-hours a day, year-round.

How much will my service cost?

The size and complexity of your HVAC issue will determine the cost. Because our trained, licensed HVAC technicians must diagnose the issue before we are able to quote you an accurate cost, we require an appointment to be set to complete a diagnostic on your system. Once the diagnostic is complete, your One Hour(R) technician will walk you through all costs using our Straightforward Pricing(R) Guide so there are never any surprise fees.

How often should I service my HVAC system?

It's ideal to service your cooling system each spring and your heating system each fall to ensure you find small issues before they become big problems.

How often do I need to change my HVAC filter?

Your filter should be changed every one to three months, depending on conditions in your home and your region's climate.

Do you offer purchase financing?

We work built relationships with several lenders to ensure our customers are able to restore comfort in their homes. Ask your technician about your financing options.

What are the advantages of a smart Thermostat?

Smart thermostats learn a household's patterns and adjust heating and cooling according to when a home is occupied, give homeowners the ability to control the thermostat remotely, and enable homeowners to reduce their energy use, saving you money.

HVAC means Heating, Ventilation, and Air Conditioning. HVAC systems refer to air conditioners, furnaces, and any unit that cools indoor spaces during the summer and warm them in the winter. In general, an HVAC system takes in air, heats or cools that air, and blows it into a room or any indoor space. While many homes have separate air conditioning and heating units, others have a heat pump that cools and heats the house. Not only do HVAC systems maintain desired temperatures, but they also improve indoor air quality and regulate humidity levels. But most importantly, these units provide comfort all year round.

What is a SEER Rating?

The SEER (seasonal energy efficiency ratio) is a measure of the efficiency of your heating and cooling system.The higher the SEER rating, the more efficiently a unit operates. The SEER rating of any given unit can range anywhere from 13 to 21.

Bringing Comfort Home

With Expert AC Services

One Hour Heating & Air Conditioning® of South County

4.82

(152118 reviews)

Heating & Air Conditioning

Services By One Hour

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Two One Hour Heating & Air Conditioning technicians standing confidently in front of a service van.

HVAC Repair, Installation & Maintenance

Heating, AC & Furnace Repairs in South County, MO

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 Knowledgable

4.82

(152118 reviews)

Michele Smith

in the last week

“One Hour Heating and Air is going to be super helpful to anyone who has issues with their A/C and heaters. They did some training at my residence, and they were fantastic! They know that we are not professionals but they way they explained the work was super easy to understand!”

Joel H

in the last week

“David (if I remember correctly) was very helpful and provided a quote for repairs that was very affordable. I also appreciate the way he explained things that felt like a person to person conversation rather than a conversation with a salesman”

Kenneth Picha

in the last week

“We needed some ventilation ducting replace due to animals who got into house and chewed up old ducting. Our Project Manager did a great job of coordinating repairs and the installation team did the work quickly and well.”

dusty holloway

in the last week

“Calvin from Duggan One Hour heating and Air-conditioning came to do a diagnostics on my HVAC. I will say he did a very thorough job and found the leak in my evaporator coil. Very impressed with the service that I received. Highly recommend.”

William Laughman

in the last week

“We have 3 heating/cooling zones in our 2300 sf home. We were having some temperature discrepancies and frankly, we weren't sure what areas were covered by each thermostat. We called One Hour Heating and cooling. Jordan came out and evaluated our AC unit and our furnace. He found a couple of issues and explained each zone covered by each thermostat. He was fantastic. Jordan educated us on how our system works. I use the word educated because he explained everything very well was not pushy and was very polite, personable and professional. We had him do the work he recommended at a very reasonable cost. We will definitely be using one hour heating and cooling for our future needs.”

William Greenwald

in the last week

“Once again, One Hour is excellent in executing their service contact. Josh did a great job of cleaning and servicing all three of my units. He further addressed any issues he found, and offered possible solutions to them. I really enjoy how thorough they are each time they come out.”

jim munn

in the last week

“Jacob did an excellent, thorough job. He didn't have the correct pump but went out of his way to get one today instead of coming back tomorrow. So now we can sleep in cool”

Tina Schmidt

in the last week

“Unfortunately, my technician wasn’t listed on the site. So I can’t mention him by name and I don’t believe he gave me his name. Can’t be too sure. Great service as always second time I’ve used this company hands-down the best. Technician was informative gave me every step that he was doing asked if everything was OK and to my liking. Worked with me around my animal and very clean will definitely be a repeat customer for the third time.”

Rick Conant

in the last week

“They came in removed my ( my boat anchor Rheam water heater ) installed a new thankless unit , a unit that will finally give us a hot second and many following HOT showers . Great job !!! We have fought this new Rheam t50 gal tank for three years along with replacing the new tank along with valves. Thankyou Thankyou . Oh the furnace you put in is fantastic too.”

Cookie Fresa

in the last week

“Chris Alegria demonstrated a high level of professionalism during our interaction and addressed all of my questions thoroughly. His expertise and willingness to assist were evident, making the experience both informative and pleasant. Based on this positive experience, I wholeheartedly recommend him to others seeking similar support or guidance. His ability to communicate effectively and provide clear answers is commendable and adds significant value to any collaboration.”

HVAC Services You Can Count On

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!

Yellow One Hour Heating & Air Conditioning service van with company branding and slogan.

'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.