Has this ever happened to you? You light a fire in your fireplace, hoping to settle in for a cozy, quiet evening of relaxation. Then, suddenly, your living room fills with smoke. It’s enough to make one panic and wonder what the heck is going on. In this post, we look at the common problem many fireplace owners face, which is why smoke flows back down the chimney.
Before getting to why smoke flows back down the chimney, let’s take a second to look at how a fireplace functions. Indoor fireplaces go back to the Middle Ages, so it’s no secret why people have so much nostalgia for them despite having access to easier-to-use heating methods like electric or gas furnaces or boilers. Fireplaces are simple machines composed of a firebox, a throat, and a chimney. And they’re simple to use. Start a fire in the firebox with seasoned logs, and oxygen from the draft keeps the fire lit while the smoke and gases exhaust up the chimney.
However, although simple to use, many fireplace owners have difficulty keeping the fire going, getting the fire hot enough, and dealing with other issues, like smoke.
Smoke blowing back down the chimney, often called back puffing or blowback, happens for various reasons. However, the primary one is that there isn’t a strong enough draft to overcome wind or airflow coming back down the chimney—too much negative airflow results in a smoke-filled living room. Having said that, what causes poor drafting, and what can you do about it?
One of the most common reasons smoke blows down your chimney is because the flue is too small. If your flue is too small, it will not be able to draw the air up and out of your home, which will cause the smoke to come back down into your living space.
Another reason that smoke might blow down your chimney is because of a blockage. If something is blocking the flue, such as a bird’s nest or leaves, the smoke will have nowhere to go but back down into your home.
Although a draft is essential to creating and maintaining a healthy and enjoyable fire, too much of a good thing can cause problems. If your fireplace is not drafting correctly, then the air will flow back down into your home instead of up and out of the chimney. The airflow needed for the fire can be affected by your home’s insulation, the flue’s temperature, wind patterns, and chimney leaks.
Finally, another possibility is that there is a hole in your chimney. If there is a hole in your chimney, then the smoke will have an easy escape route and return to your home instead of going up and out of the chimney.
Another possibility is that the damper in your chimney is not working correctly. The damper is designed to keep the cold air out and the warm air in, but if it is not working correctly, then the warm air can escape, and the cold air can come in, which can cause the smoke to blow back down into your home.
Preventing smoke from coming back down the chimney and into the house depends on what’s causing the problem. If the chimney is too short, you can extend it a few feet. If the flue is cold, you can prime it by making a torch from newspapers and heating it before starting your fire. If the flue is blocked, call a professional chimney sweep for cleaning. Finally, if it’s a drafting issue, consider opening a window or running an exhaust fan to help.
FlameMaster is your local, trusted chimney sweep. We’re family owned and operated, and our core mission is bringing our customers top-rated service at reasonable prices.
Our technicians are certified, so you can trust the work they provide. If you’re having difficulty with your fireplace or need routine cleaning and maintenance, call us at 719-661-3277 or fill out our online form.