The only reason smoke goes up the chimney is because it is lighter than cold air (which is more dense) and because you have a properly sized chimney for the smoke to exit the residence. A smoky fireplace is the most common fireplace problem our customers experience. Whatever the duration or cause of a smoky fireplace, it is important to put a stop to it because it can be dangerous for combustion byproducts to enter your home. If you get a puff of air on the outside of the house that is equal to or greater than the force of the smoke going up the chimney, you will experience acute SITF (Soot In The Face).
These are puffs of air that come down the chimney and blow the smoke in your face and creates a smoky fireplace. Make sure you have a chimney cap. Your cap is your first defense. If you don’t have a chimney cap on your chimney, you may obtain one from us to avoid smoky rooms.
I know it may sound unbelievable, but the solution here is to (drum roll please) open the damper to avoid a smoky fireplace. If you had to look this one up online and if you are reading this now… well… you have our sympathy.
When a chimney gets clogged, the flue can become so narrow that combustion products can’t properly exit the chimney, resulting in a back draft causing a smoky fireplace. There are many different types of chimney obstructions which cause a smoky atmosphere, and a few examples are: an animal builds a nest in your chimney, there is an excessive accumulation of creosote, masonry is deteriorating and falling into the flue, and leaves or other types of debris have collected in the flue. Clearing the blockage can help combustibles escape properly and solve smoky fireplace problems.
A cold brick chimney or a cold metal factory built chimney will create a chilling effect on the exhaust gases. The exhaust gases will no longer be lighter than the surrounding cold and dense air, so they will essentially come back down the flue to create a smoky fireplace, because your house is a better chimney than the outside world. This may result in acute SITF. If you believe that your chimney has a cold, or the flu, we recommend that you immediately hang up and call… someone.
In some rare cases we have noticed that clients have too many mechanical exhausts in the residence and not enough planned air infiltration locations (“make up air”, or “outside air kits”). A smoky fireplace is the result. Imagine your house as a box, tightly sealed. Now imagine your clothes dryer and the bathroom fan are on simultaneously. These mechanical fans are pumping air out of your box. Unless air is intentionally designed to enter your residence somewhere else, the fireplace will do nicely, meaning your fireplace will run backwards, and air will come down the chimney in order to “make up for” the air that is being pumped out (we assume here that the box, i.e., your house, is strong enough to not collapse under the negative pressure generated by the bathroom exhaust fan and the clothes dryer). Solution: provide a source of air for the mechanical appliances, and also for the fireplace to draw air in for combustion.
As you can see there are a number of issues that can create a smoky fireplace. It is our desire that you will read and share this humorous article with your friends and family. And possibly you might even hire a Certified Midtown Chimney Sweep to come inspect your smoky fireplace!