Stove Type The Flue Gas Temperature at the The Flue Gas Flow is (gr/sec.)
rated output is (°C) relative to 20° C
Ø4 270 4,1
1.9 Draft conditions
If smoke spillage occurs when the re door is opened, it is probably due to poor chimney
draft. This type of stove requires at least 12 pa of chimney draft to achieve satisfactory combustion and smoke spillage prevention. However, in cases where the stove door is opened
too vigorously you could expect that slight smoke spillage may occur.
Draft conditions
The chimney’s draft is the resulting eect within the ue caused by the dierence in
temperature within the ue and the cooler temperature outside. Other factors that
can inuence the level of draft include the length of the ue, insulation of the chimney, adverse weather conditions or tall buildings or trees nearby the ue terminal.
Poor draft occurs when:
• The atmospheric temperature dierence is too low, e.g. a poorly insulated chimney.
If the chimney is excessively cool, it may help to ‘prime’ the ue before the re is
lit. Just place a screwed-up sheet of newspaper in the ue-ways of the stove and
ignite.
• The outside temperature is too high, e.g. during the summer months.
• There is no air movement (wind) outside.
• The chimney is not tall enough, with the result that the terminal sits in the lee of
the roof surface or in the vicinity of tall trees or neighbouring buildings. These conditions are also associated with downdraft where the ue gases are pushed back
down the chimney.
• Flue draft is diluted by residual air entering the chimney, e.g. due to inadequate
ue-pipe joints or leaks at the cleaning door or ue collar.
• Unsealed, unused replaces are connected to the chimney.
• The ue is blocked, e.g. by soot, due to inadequate cleaning, loose debris or even a
birds nest.
• The house is too tightly sealed (see section on Fresh air supply).
A good draft is achieved when:
• The temperature dierence between the chimney and outside is high. This also applies during ring, when the need is greatest.
• The weather is clear and there is a good wind.
• The chimney is of the proper height, i.e. minimum 4 meters over the stove and the
termination adequately clear of the roof line.
If you have any doubts, you may want to have your installer measure the draft in the chimney.
If there is too much draft from the chimney, a damper device can be installed in the chimney
to reduce the draft.
Please note that this damper device must not close the aperture area in the chimney entirely.
There must be a clear opening of at least 20 cm2 when the damper is closed.