5
CI-2013-05-14
780mm
505mm
638mm
3.3 Draught conditions
If smoke comes out of the stove when the fire door is opened, it will be due to the poor draught in the chimney.
This type of stove requires at least 12 Pa of chimney draught to achieve satisfactory combustion and to prevent
smoke from escaping. Smoke may, however, escape in any event if the stove door is opened during vigorous
firing, so this should be avoided.
If in doubt, you may want to get your chimney sweep to measure the draught in the chimney.
3.3.1 Draught
The draught in the chimney is the result of the difference between the high temperature in the chimney and the
cooler temperature outside. Other factors that determine whether sufficient negative pressure can be produced to
create a draught include the length and insulation of the chimney, and wind and weather conditions. In the
unusual event of adverse weather conditions that cause downdraught, the appliance must not be used.
3.3.2 The draught will be reduced when:
- The temperature difference is too low, e.g. in connection with a poorly insulated chimney. If the
chimney is cold, it may help to light (burn up) a rolled-
up newspaper in the chimney‟s cleaning door.
- The outside temperature is too high, e.g. during the summer.
- There is no wind.
- The chimney is not tall enough, with the result that it sits in the lee of the roof surface or tall trees.
These conditions are also associated with the greatest risk of smoke coming back down the chimney.
- Air is entering the chimney in undesired places, e.g. through cracked joints or leaks in the cleaning
door or the flue pipe.
- Unsealed, unused fireplaces are connected to the chimney.
- The flue pipe and chimney are clogged up with soot due to inadequate cleaning.
- The house is too tightly sealed (please see the section on Fresh air supply).
3.3.3 A good draught is achieved when:
- There is a big difference between the temperature in the chimney and outside, i.e. when the need for
heating is greatest.
- The weather is clear and there is a good wind.
- The chimney is of the proper height, i.e. Minimum 4 metres above the stove, and clear of the spine of
the roof.
4. Chimney sweep
You may need to consult your local chimney sweep before installing the stove. After the stove has been installed,
advise the owner/user to have the chimney system checked and swept at least once a year. If the chimney
system has not been used for some time, it should be inspected for cracking, bird nests, etc. before it is put back
into use.
5. Stove placement/clearance and floor protector requirements
Clearance requirements apply only if the stove is placed near to combustible materials. Permitted clearances to
combustible materials are also indicated on the data plate on the rear of the stove.
