Newman Easedale 5 SE, Инструкция по установке и эксплуатации

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2.9 Chimney Draft
Refer to current National laws, Building Regulations, & any Rules in Force, including BS
8303 and BS EN 15287-1:2007. Also refer to Approved Document J (England & Wales)
The recommended chimney draft is 12.5 Pa when the stove is operating at its nominal heat output.
If smoke spillage occurs when the fire door is opened, it is probably due to poor chimney draft.
This type of stove requires at least
12.5 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.
If you have any doubts, you may want to have your installer measure the draft in the chimney.
Important: If the flue draught is excessive this will cause over firing and rapid burning of the fuel,
this will impair controlling the burn rate which is a dangerous situation and also cause damage to
the stove, the stove warranty would be invalidated in this situation. If the flue draught is excessive
consult a Hetas registered stove installer or (equivalent for other nations & countries). Do not use
the stove until the situation has been remedied.
Draft conditions
The chimney’s draft is the resulting effect within the flue caused by the difference in temperature
within the flue and the cooler temperature outside. Other factors that can influence the level of
draft include the length of the flue, insulation of the chimney, adverse weather conditions or tall
buildings or trees nearby the flue terminal.
Poor draft occurs when:

The atmospheric temperature difference is too low, e.g. a poorly insulated chimney.

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 neighboring buildings. These conditions are also
associated with downdraft where the flue gases are pushed back down the chimney.

Flue draft is diluted by residual air entering the chimney, e.g. due to inadequate fluepipe joints
or leaks at the cleaning door or flue collar.

Unsealed, unused fireplaces are connected to the chimney.

The flue is blocked, e.g. by soot, due to inadequate cleaning, loose debris or even a birds nest.

The room to which the stove is installed is too tightly sealed. See section 2.8 Ventilation
Fresh air supply).
A good draft is achieved when:

The temperature difference between the flue way or chimney and outside atmosphere is high.
(Higher temperature in flue way or chimney and cooler temperature to external atmosphere).
This also applies during firing, when the need is greatest.

The weather is clear and there is a good wind.

The chimney is of the correct height.

The room that the stove is installed is adequately ventilated.