Morso 5660 Standard Insert, Instructions For Installation And Use Manual

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9
DK ENG
1.8 Draught
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 1 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.
The flue gas temperature at the rated output is 86°C relative to 0°C.
The flue gas mass flow is 7.1 grammes/second.
If in doubt, you may want to get your chimney sweep to measure the draught in the chimney.
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.
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).
A good draught is 2achieved 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.