Occasionally, heating by means of a wood-burning stove can be problematic.
Many of the problems can be avoided by knowing about the following problems beforehand:
INSUFFICIENT CHIMNEY DRAUGHT
In order for the stove to function the glass must be kept clean and sufficient oxygen supplied for combustion. This requires sufficient chimney draught. Insufficient chimney draught can be a result of the chimney being too low or inadequate.
A NEW STOVE DOESN’T FUNCTION
New stoves have a much higher level of efficiency that old stoves. This greater efficiency is achieved by reducing the temperature of the flue gas before it leaves the stove. This means that the temperatures in the chimney and, consequently, the draught are lower than they were previously.
IMPACT OF EXTERNAL WINDS
The height of the chimney should be suited to the height of the roof. External circumstances can be the cause of a poor draught in the chimney.
1: The chimney is too low in relation to the roof.
2: Leaky joints or cleaning hatch in the chimney system.
3: Other buildings create turbulence over or a downdraught in the chimney.
4: Large trees can “shadow” the wind and create a bad draught.
A vacuum can be created in the house so that the chimney does not extract the smoke.
This is particularly prevalent in very airtight houses. See the section “External combustion air”.
The connection between the stove and the chimney must be airtight. The more bends there are and the sharper they are the more resistance and less draught there will be.
SOOT accumulations from chimney cleaning can block the smoke extraction ducts.
BIRDS’ NESTS, typically jackdaw’s nests, can block your chimney. Always check that there the air can flow freely through your chimney before the start of the heating season.
ELEMENTARY OPERATING ERRORS
Firing up with an open ash drawer of to much primary air can cause the stove to overheat with, for example, white windows as a result.
Overfilling of the combustion chamber can cause both the tertiary air and the air wash system to function as primary air whereby combustion is uncontrolled.
If the door is not closed following firing up it can lead to overheating.
Firing up with unsuitable fuel can damage the stove, for example, pressure impregnated wood and plastic create hydrochloric acid which rots the iron, the insulation and the glass.