While most people think that simple “smoke” results from an initial fire in a fireplace, sometimes it’s more than that. What’s called “flue gas” can result from the primary combustion, and it consists of steam, vaporized, unburned carbon-based by-products known as vaporized creosote. As this “flue gas” travels upward through a chimney, it goes through the relatively cool flue where condensation takes place. Like warm breath on a cold mirror, the cool surface temperature of the flue causes the carbon particles in the warm vapor to solidify. This solid material is called creosote. It’s usually black in appearance, and exists in 3 different stages. All stages are highly flammable, and all stages can exist in your chimney.
1st stage - fine black powder
2nd stage - drippy tar / crunchy chunks
3rd stage - shiny glazed hard material
When an older fireplace insert is vented into a masonry chimney, often times the flue is too large. This increases the smoke’s “residence time” and decreases draw.
In these cases, the flue rapidly builds up creosote, as the large air space cannot get hot enough. This causes rapid creosote condensation.
Simply put, the longer the smoke is in the flue, the more likely creosote will form. If the air supply of a fireplace is restricted by closed glass doors, or by failure to open the damper wide enough, creosote will build up rapidly.
As rule of thumb, never use wet wood to fuel your fire, it creates a lot less heat, and it doesn’t do a very good job of burning the available fuel in the wood. The “smoke” of unseasoned wood is heavily laden with unburned creosote. Because unseasoned wood causes the whole system to burn cool, the creosote laden flue gas quickly condenses on the surface of the flue. Dry, well seasoned wood is the only wood that should be used in any chimney system. Tar-like creosote found in an open chimney system is more often than not ,caused by burning wet or unseasoned wood.
Believe it or not, the main cause of creosote in your chimney is a cool flue temperature. Metal, prefabricated zero clearance fireplace chimney’s are extremely prone to creosote build up. Their light sheet metal construction actually causes the interior flue temperature to be abnormally cool. Due to this, creosote condenses inside a prefabricated chimney at rapid rate.
Around 25,000 fires a year occur in homes with chimney problems. Much of this has to do with creosote buildup. These fires can easily be prevented with a simple chimney cleaning.
If you’re concerned about the creosote in your chimney, please feel free to contact Atlanta Air Duct Cleaning, your premier choice for Atlanta chimney cleaning!
Having a fireplace can make an already comfortable home, all the more pleasant. It keeps you warm during the chilly months, but also creates a welcoming environment for you and your family to gather and spend quality time together. As great as your fireplace is though, it still needs to be cleaned regularly, or else you put your family at risk to spontaneous fires and even poisoning.
Many people set a specific rule on chimney cleaning: “once every 50 uses”. This is a common rule of thumb, and it’s a decent way of keeping your chimney in working order. However, to get the most out of your fireplace, you should gauge exactly how dirty the chimney flue is.
The things that are going to make your fireplace the dirtiest is if you are burning fires using green wood (freshly cut wood that hasn’t had time to dry), slow cool fires, or slow cool small fires in conjunction with green wood. With these fireplace practices, you can clog up the chimney with creosote, which can actually catch on fire if enough accumulates, and it can burn the whole house down.
Even a chimney that has not been used for a wood burning appliance can become blocked by dead rodents or insects, such a hornet’s nest. Don’t forget to inspect the flue before lighting the first fire of the season, because animals and insects could have obstructed the flue over the summer. If you have a properly screened cap on your chimney top, you’ll keep out the animals but unfortunately not the insects.
Part of regular oil-fired heating service includes dis-assembly and cleaning of the flue vent connector. Ask your heating service tech to check the chimney itself and order a cleaning if needed. Gas fired heating appliance chimneys ought to be inspected regularly. A blocked off gas-fired chimney can create a serious risk of improper gas appliance operation, which is likely to produce dangerous, potentially fatal carbon monoxide.
Once you’ve had your chimney cleaned, future cleanings can be scheduled based on how many fires you’ve had, and the type of wood you’re burning.
Whether you want a simple inspection, or you’re chimney is in desperate need of a cleaning, please Contact Us Today. We’re the authority in Atlanta chimney sweep service!