Some stoves seem to work just fine except when it is wet out. If this seems to be the case, pay close attention to the weather when you have smoking problems. It is easy to confuse wind-related problems with rain-related problems. If it does appear to be the wetness that does it, here are some possibilities:
Cold, Wet, Exterior Chimney
If you were stuck out in the rain, cold and wet, you probably wouldn’t feel particularly energetic. Well, it’s the same thing for chimney draft in chimneys built on the outside of the house. Wet masonry around the flue draws heat away from the smoke and gasses in the flue, reducing the draft, and making it much harder to heat the flue in the first place.
The solution, in most cases, is relatively simple: First, install a chimney cap on the flue if you don’t already have one. A cap will keep most of the water out of the flue.
Second, call your chimney professional and arrange to have a water repellent applied to the exterior brickwork, to prevent water from soaking into the chimney.
No Chimney Cap
Even if the chimney is built up the center of the house, so that most of it is protected from the rain, a chimney with no cap is like an open skylight: rain will run freely down the flue, drawing heat from the smoke and gasses in the flue and reducing draft. Get a cap.
Warm Outside: Cold Inside. Sometimes on raw, rainy spring or fall days, it is actually warmer outside the house than inside. If this is the case, draft conditions, especially when starting the stove, will be adverse. You will probably need to spend some extra time priming the flue, and you may need to keep a fairly brisk fire going for a while, to warm the flue properly.
Smoking in Other Rooms
If you find smoke entering a room other than the room where the stove is located, see the section on Smoking in Other Rooms for causes and solutions.