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fireplace that allows smoke to escape into the room (back puffing) is a nuisance and a downright danger because fireplace smoke carries odorless but deadly carbon monoxide. Diagnosing the cause of your smoky fireplace is essential to finding the most efficient and cost effective solution to your back puffing.
Here's what to do if your fireplace smokes:
First, make sure the fireplace is getting enough air to replace the hot gasses it is sending up the chimney. Shut off any exhaust fans than may be running, even upstairs in your home. Those
exhaust fans are pulling household air (or maybe your fireplace's smoke) to the fans. If shutting off exhaust fans doesn't stop the back puffing, test by opening a door or window near the fireplace
to see if that corrects the problem.
If the fireplace allows smoke to escape into your room only on windy days, the answer is to install a Vacu-Stack Chimney Cap. As the wind passes through the
Vacu-Stack chimney cap, it creates a vacuum above the flue. The harder the wind blows, the harder the Vacu-Stack "pulls" the smoke up your chimney, so all the smoke goes up your chimney and none
goes into your room.
If the smoky fireplace problem happens on calm days, too, there are three things you can do, in the order of the least expensive and the least certain to the most expensive and absolutely
certain:
If the area of your fireplace at the front (width times height in square inches) is more than ten times the area of your flue, you can install a Smoke Guard to reduce the size of the fireplace
opening. (To compute the area of your flue, if it is rectangular or square, multiply the flue's length by its width. If it is a round flue, use the radius, which is half of the
diameter. Multiply 3.14 x radius x radius.) Installing a Smoke Guard can better proportion the opening of your fireplace, allowing the flue to work more efficiently, eliminating your smoky fireplace problem. The Smoke Guards come in either brass or black.
If the first step, increasing the air supply works, you can install an air supply ventilator to let fresh air into the room where the fireplace is.
To cure any and all back puffing problems, you can install an Exhausto Fan. An Exhausto is a weatherproof exhaust fan that mounts on the top of your chimney. These powerful fans create
a forced air draft that sucks the smoke from the flue, ending forever the problem of a smoky fireplace. Exhausto Fans can even end tricky draft problems found with see-through
fireplaces and poorly proportioned corner fireplaces. Also, count on Exhaust Fans to put an end to problem odors from your chimney.