Does your wood stove push smoke back inside your home? Sometimes people will see smoke when lighting a wood stove, while it is burning, or when they open the door of the stove to add wood or tend to the fire. The wood stove burns the wood, generates heat, and then sends smoke up and out the flue. When the smoke is not being drawn up and out the flue very rarely is it a problem with the stove itself. Most likely the problem lies with the flue system, the operator, or the draft. Let's cover some common problems that can lead to a smoking wood stove and their solutions.
When you are experiencing a smoking problem with a wood stove, one of the first things you should do is check your chimney cap. Even with EPA certified stoves, they can get clogged, especially with spark arrestors. When it is cold and damp, the spark screen can become sticky and begins to collect more particles than it should producing a clog. If you check out your chimney cap and it is not clogged, then that is not the cause of your issue and you will have to look into it further.
One key to your smoking problem will be when you are seeing the smoke from your wood stove. Are you seeing wood stove smoke only when you start a fire, only when it is windy, intermittently, or are you seeing smoke all the time?
If your wood stove smokes only when you are trying to light it, the first thing you should consider is the inside temperature of the stove. If the inside of the wood stove is cold, the cool air will funnel down the chimney and into the wood stove where it will remain trapped by the doors. To prevent this from happening, open the doors on your wood stove and allow the wood stove interior to heat up for at least 30 minutes before you attempt to start a fire in it. Opening the doors will not only pre-heat the wood stove it will also jump start the draft and get it moving upwards. Another reason that you could be seeing the smoke, only when starting your wood stove, is that the firewood is wet or unseasoned.
If your wood stove is only smoking when it is really windy, your chimney may be too short. Building codes require chimneys to be at least 2 feet taller than any object within 10 feet, such as the roof surface or a dormer, or 3 feet taller than the peak of the roof. In some cases, these suggested heights may not be adequate to allow the chimney to draw air properly. Homes that are surrounded by trees or hills, or close to large bodies of water, may need to extend the chimney height higher than the required 3 feet. Taller chimneys work better since shorter chimneys will not pull the smoke out of the home very easily.
If your chimney extends the required height above your roof and wood stove smoke is still back puffing into your home, you may need to put a special chimney cap on the pipe. There are chimney caps that are specifically designed to stop wind from blowing into the chimney, regardless of the wind direction. For example, VacuStack chimney caps deflect wind turning it into more of a Venturi effect causing the smoke to be sucked out of the chimney.
Raising the height of your chimney could also be a solution to downdraft problems that can cause your wood stove to smoke intermittently. Often downdraft will only occur in certain conditions, so you might find that it is only on days when the wind comes out of the North that the stove smokes in puffs due to downdraft. If raising the height of the chimney does not work, affixing an anti-downdraft cowl will do the trick.
If your wood stove smokes all the time, there are several things that could cause your wood stove to smoke continuously including:
- Un-swept or blocked chimney
- Competition with another chimney or extractor
- Poor ventilation
- Excessive fireplace opening size in relation to the flue size
- Incorrect size of the chimney pot
- An unlined or cold (un-insulated) chimney
- Pressure difference around building
- Insufficient chimney height and therefore inadequate draw.
The easiest way to figure out which of the above causes is the reason for your wood stove smoking is to make a checklist and try to eliminate each cause. If your wood stove and chimney has not been cleaned recently, a good cleaning session may cure your smoking fireplace.
Northline Express is here to answer all your questions. Feel free to give us a toll free call at 1-877-734-2458 or email us at firstname.lastname@example.org.