Bad draw
A bad draw is often caused by a contaminated connector or flue. Check all existing valves in the connecting pipe are in the correct (open) position.
When smoke comes back into the room this can be because the flue is not yet warmed up. The chimney only has a good draw if the smoke is warmer than the outside air. Heat up the flue by rolling up a piece of newspaper into a torch and keep it in the flue until the smoke is going in the right direction. Chimneys that run along the outside of the house, particularly, require some pre-heating.
Factors influencing the draw
The build of the flue
- The diameter of the chimney must not be smaller than the diameter of the outlet of the stove.
- A higher chimney means a better draugh. If the draugh is not sufficient sometimes, a higher chimney is sufficient to improve the draw.
- A chimney with a round insert pipe normally gives a better draugh than a square.
- The use of elbows in the pipe reduces the pull. If there are bends to be used, 2 x 45 ° is preferred over 1 x 90 °.
The supply of combustion air is of essential importance for the tensile
An open fireplace needs about 300 m3 of air per hour, and a "closed" fireplace approximately 30 m3 per hour.
A kitchen fan or hood sucks much more air than a chimney. This can lead to a kickback. In other words, the kitchen hood draws air into the room coming from the chimney, thereby drawing smoke into the room.
Opening a window should solve this problem immediately.
Influence of the wind
The draw can be disrupted by:
- high trees
- cliffs
- high buildings
This problem can usually be solved by making the chimney higher. In extreme cases, an exhaust fan can be installed. A draugh regulator can stabilize the draugh of the chimney.
Reduction of draw
At high temperatures, the fireplace provides a strong pull. The best results are achieved when the height and diameter of the chimney are aligned with the device in use. If the pull is too strong, the heat can quickly be sucked into the chimney. Too strong a draft can be adjusted with valves, draugh regulators (insert pipe or chimney) or restrictors. The use of multiple bends in the flue pipe reduces the pull.