Bad draw

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Bad draw is often caused by a contaminated connector or flue. Check if any existing  valve in the connecting pipe is in the correct (open) position.

When smoke comes back inbto the room this cab 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 to keep it in the flue until the smoke is going in the right direction. Especially chimneys that run along the outside of the house 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 oven.
- A higher chimney means a better draft. If the draft is not sufficient sometimes a higher chimney it is sufficient to make higher the chimney.
- A chimney with a round insert pipe normally gives a better draft 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

A fireplace needs about 300 m3 of air per hour, a "closed" fireplace approximately 30 m3 per hour.
A kitchen fan or hood sucks much more air than a chimney. This can lead to 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 will 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 should be installed. A draft regulator can stabilize the draft 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, draft regulators (insert pipe or chimney) or restrictors. The use of multiple bends in the stakes pipe reduces the pull.

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