Why is my furnace blowing cold air?

Common causes include a dirty flame sensor, a failed igniter, a clogged air filter restricting airflow, or a thermostat issue. If your Dunwoody home's furnace runs the blower but doesn't produce heat, the burner may not be lighting. A technician can diagnose the specific cause.

Is a banging noise from my furnace dangerous?

Banging or popping sounds when the furnace starts up often indicate delayed ignition — gas builds up before igniting. This can stress the heat exchanger and should be checked by a technician. Other noises like squealing or rattling usually point to blower motor or belt issues that also need attention.

How often do furnaces need repair?

A well-maintained furnace may run for years without issues. In Dunwoody, where furnaces sit idle during the long warm season, having the system inspected before winter catches problems early. If your furnace needs repair more than once a season, it may be nearing the end of its useful life.

Can I troubleshoot my furnace before calling?

You can check a few things: make sure the thermostat is set to heat and the temperature is set above the current room temperature, check that the circuit breaker hasn't tripped, and replace the air filter if it's dirty. If the furnace still won't work after those steps, call a technician.

Should I repair or replace my furnace?

If the repair cost is reasonable and the furnace is in otherwise good condition, repair makes sense. If your Dunwoody home's furnace is old, needs frequent repairs, or has heat exchanger problems, replacement may be the more practical choice. A technician can help you decide.

Always On Time

Furnace Repair in Dunwoody, GA

One Hour Heating & Air Conditioning® of North Atlanta

Furnace Repair in Dunwoody, GA

Furnace repair in Dunwoody gets your heating system back up and running when cold weather makes a broken furnace impossible to ignore. Even though Georgia winters are milder than up north, Dunwoody still gets cold enough that a home without heat is uncomfortable and can be unsafe — especially at night.

Common Furnace Problems in Dunwoody

Because Dunwoody's heating season is shorter than in colder climates, furnaces here often sit idle for months at a time. When they finally kick on in the fall, problems that developed during the off-season show up all at once. Ignition failures, dirty flame sensors, clogged filters, and worn blower motors are among the most common issues. The furnace may cycle on and off repeatedly, blow lukewarm air, make unusual banging or squealing noises, or refuse to start at all. In some cases, a simple part replacement solves the problem. In others, the issue may point to something more serious that needs professional attention.

How Furnace Repair Works

A technician starts by listening to your description of the problem, then performs a thorough inspection of the furnace — checking the ignition system, flame sensor, heat exchanger, blower motor, thermostat connection, and gas supply. Electrical components are tested, and the system's safety controls are verified. Once the issue is found, the technician explains the problem and walks you through the repair before getting started. Most furnace repairs in Dunwoody homes can be completed during the same visit. For safety issues involving the heat exchanger or gas connection, the technician will shut down the system and explain your options.

Don't Wait When Your Furnace Needs Repair

It's tempting to put off furnace repair in Dunwoody's mild climate, but small problems tend to get worse. A furnace that's struggling now will work even harder when the temperature drops further, and the added strain can turn a minor repair into a major one — or cause the system to fail completely on the coldest night of the year. If your furnace is making strange noises, cycling oddly, or not putting out enough heat, call for a repair before the problem grows. Getting it fixed now means you won't be caught without heat when you need it most.

About Dunwoody

Dunwoody's winters are mild by national standards, but temperatures drop into the 20s and 30s often enough that reliable heat is a must. Cold snaps can arrive suddenly, and the shift from warm afternoons to chilly nights catches homeowners off guard. Because furnaces in Dunwoody sit idle for much of the year, they're especially prone to startup issues when the heating season begins. Neighborhoods from Tilly Mill to Womack Road and throughout the city depend on functioning furnaces during the cooler months.

Serving Dunwoody and Surrounding Areas

Our furnace repair service covers Dunwoody and surrounding communities including Sandy Springs, Brookhaven, Chamblee, Doraville, Roswell, and Johns Creek. We serve homeowners throughout the Perimeter area and North Atlanta.

Call (404) 689-4168 to schedule service.

Visit our office:

One Hour Heating & Air Conditioning
1360 Union Hill Rd Ste 5F, Alpharetta, GA 30004
(404) 689-4168
Open 24 hours

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Excellent service

Helen Albanese

in the last week

We had central AC added to our home 5 years ago. We decided to get an AC and furnace tune up before the summer. Matt, the technician from One Hour Heating and Air, was on time and polite. He pointed out that our furnace filter had not been changed since 2022. Big oversight by me. Matt explained how the air flows through the furnace and the direction the filter needs to be placed. I marked with a sharpie on the furnace an arrow so I would remember next time. Good piece of mind. Positive experience.

Justin Low

in the last week

I cannot recommend this HVAC company enough. The technician showed up exactly on time and was patient throughout the entire visit. They took the time to answer every single one of my questions thoroughly, making sure I felt completely comfortable with the process. What I appreciated most was their honesty—they gave me several clearly explained options for both repairing my current unit and replacing it. Best of all, they were not pushy and never once tried to upsell me on things I didn't need. It is rare to find such genuine, reliable, and pressure-free service these days. A 5-star experience from start to finish.

Paul Yi

in the last week

Best HVAC team in King County. Professional, reliable, and honest. Alex, the owner, takes great care of his customers. Highly recommend.

Denis

in the last week

I was initially skeptical of working with a franchise, but I was really impressed by how professional, helpful, and punctual their technician, Matthew, was throughout the visit. Pricing was reasonable and I will definitely be going with them for any future HVAC needs.

Max B

a week ago

Really good experience with One Hour. Alex was super communicative from the first call, got us on the schedule quickly and kept us in the loop the whole time. Marklus came out and handled the repair. Technically solid and left everything cleaner than he found it. Never felt pressured to buy anything extra which was refreshing.

vivek savsani

a week ago

We had our heating system stop working during the extreme snow storm, and this company responded quickly. Joe Bonness, who is an expert technician arrived on time, diagnosed the issue fast, and fixed it efficiently. He explained everything clearly and made sure the heat was working perfectly before leaving, even though it was late around midnight. We are very grateful for the quick and professional service during such freezing weather. Highly recommend their service!

Neha

a month ago

Huge thanks to my neighbor Chris for coming over late at night to fix my AC unit when it stopped working. I caught him and his family on the way out and told him my problem. He ended up leaving his plans early and took the time to figure it out and got it running again quickly. It meant a lot that he was willing to help out so late. He even gave me a few tips to look out for in case anything else happened. Super knowledgeable and a great neighbor to have! Give that guy a raise!!

Zaria Smith

a month ago

Tim was great. I can’t say enough good things. He came out to do a routine maintenance and unfortunately, I had to replace my furnace due to wear and tear. This happened on Friday, and he was at my house bright and early Monday to install the new furnace. He was pleasant the entire time, and very informative throughout. Thank you so much.

Sindel Garcia

a month ago

I will start by saying that KC was very professional explaining all aspects of the whole job that his team was going to do as far as to what we needed concerning a furnace rather we should repair or replace the existing furnace which by the way was 26 years old. Zo the service installer was quite thorough with the entire job, also Areej another technician did a spectacular job with cleaning all of the air ducts with detailing each step of the way up to and including the dryer vent as well a fantastic job was done. Although the job was extended one extra day was not a problem the problem came about when they informed us that they were going to return the next morning by 10am and by 11am we hadn't heard from them when a simple courtesy call with an eta would have gone a long way instead of me having to place a call to them. Overall the job was complete with a new furnace that was installed and the job was well done.p I would highly recommend One Hour Heating & Air Conditioning of Naperville.

Gerald Moody

a month ago

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