The Gas in My Fireplace Is Very Yellow & Producing Black Smoke

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Wood-burning fireplaces aren't the only types with safety issues -- gas fireplaces have safety issues, too.
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A gas fireplace eliminates the work involved in lighting a wood log and getting a fire started. However, gas fireplaces are not entirely task and trouble-free. If the flame in your fireplace changes from its normal blue color to yellow or the fireplace starts emitting smoke, don't ignore these occurrences. At their most serious, yellow flames and black smoke may signal the presence of high levels of carbon monoxide, a potentially lethal gas. At the least, they are signs that your fireplace needs servicing to keep your family and your home safe

Yellow Flame

Gas companies typically show a blue flame on their logos and television commercials. That's for a good reason. A "healthy" and correct gas flame should burn blue. A yellow flame can be an indication that the burner for the gas logs is dirty, or a sign of another combustion-related problem. As a result, gas and air are not mixing properly. That causes the flame to burn with a yellow color, instead of blue. Contact your local natural gas provider and to schedule an inspection of fireplace. In the meantime, stop using the fireplace until it is checked out thoroughly.

Black Smoke

If your gas fireplace is venting black smoke into the room, you need to check the position of the logs and the screen and have your fireplace serviced. In most cases, black smoke is a sign of a ventilation problem. When logs are not aligned properly, they can produce smoke and soot. Black smoke is also a sign of problems with your damper, flue or draft. The damper may not be open enough, the flue may be blocked and/or the draft flow may be inadequate. Contact a technician to have your fireplace serviced.

Older Gas Fireplaces

If you have an older gas fireplace or a gas starter that was manufactured prior to 1980, it may not be equipped with an OSD (Oxygen Safety Detection) device. An ODS system regulates the flame characteristics so the flame maintains a consistent blue color. An OSD detector will also shut off the pilot if it senses a problem with the flame. Upgrade or retrofit your fireplace, if possible, to include an OSD detector by a licensed fireplace technician.

Ventless/Vent-Free Fireplaces

Smoke issues can arise more frequently with ventless, or vent-free, fireplaces. When a fireplace has no chimney or vent to exhaust the smoke from out of the home to the outdoors, the smoke has no where to exhaust itself other than inside your home. As a result, ventless fireplaces exhibit ventilation problems more frequently than vented fireplaces that work in conjunction with a chimney system or exterior ventilation pipes. When the smoke from a ventless fireplace is black, that often signals a combustion problem. Have your fireplace inspected and serviced immediately.


Cheryl Munson

Cheryl Munson has been writing since 1990, with experience as a writer and creative director in the advertising industry. She holds a Bachelor of Arts in journalism with a focus on advertising from the University of Wisconsin in Madison.