Most people don’t understand how many exterior influences affect how wood burning appliances perform. Many things inside and outside the home affect how wood burning fireplaces, stoves, and inserts work.
Smoke is taken out of the home by draw, which is a change in air pressure: warmer air rises and takes products of combustion out the flue to the exterior. If the outside air is colder and more suppressive, this can be harder to overcome. The same can be said for wet, dense, foggy weather.
Of course, this is when we want to use the fireplace most, so proper burn habits are imperative.
Inside the home there are factors that affect performance as well. Many homeowners may not realize it. Two-story homes can have a natural updraft as warm air inside rises; this may affect the draw of the stove or insert.
Exhaust fans that mechanically remove air from the home—such as bathroom fans, clothes dryers, and kitchen exhaust fans—all suck air out of the home. The fans can overcome the gravity in the chimney, often drawing smoke into the home.
Before calling your chimney professional, consider what else may be affecting the appliance’s performance. If a problem persists, contact the professional to ensure it is safe to use or to get tips on how to improve the situation.