POÊLE À GAZ GODIN ref. 3428
7
THE FUNCTION OF THE CHIMNEY
The chimney is of prime importance and all causes likely to reduce the draught must be
eliminated as far as possible. If the draught becomes too weak it can cause blowbacks of
smoke in the appliance, which could cause serious accidents. A temperature switch is
installed on the cast iron outlet in order to detect any back draught. If such phenomenon
should append, the switch will send a signal to the valve and gas admission would stop. A
good chimney is basic to the proper functioning of any stove. The chimney carries the smoke
and gases safely up through the house and roof, and out into the atmosphere. It is the
chimney’s draft that draws air into the stove and enables the fire to burn. The draft is
governed by the height of the chimney and its cross-sectional area. To function both properly
and safely a chimney should extend at least two feet above any part of the roof that is within
ten feet of the chimney.
To obtain a satisfactory draught, the chimney must remain hot, be perfectly sealed and
unblocked, have a constant section, and not have sharp bends. A chimney’s draft is
determined not only by its size, height, and other physical features - it also depends on the
difference in temperature between the inside of the chimney and the outside air. If the
chimney has not been in use for some time and is cold, or the weather is mild, as in spring or
fall, you may find your stove hard to start, or smoky - especially if you have a large chimney,
or one located on the outside of the house. In such a case, avoid the premature conclusion
that the stove or chimney is defective. Allow the stove to burn slowly for a day or two, heating
the chimney.
No matter how good a chimney’s natural draft, to draw properly, it must have a supply of air. If
your house is tightly constructed or insulated, so there is a little infiltration of outside air, you
may need to provide a separate source of outside air near the stove. Sometimes, a chimney
must ‘compete’ for air supply with other chimneys in the house, such as the fireplace or
furnace chimneys, or with the natural draft of the house itself. (This house draft is sometimes
called ‘false draft’ and is caused by warm air rising and exiting through attic vents or eaves.)
These competing drafts may weaken or even reverse the draft in the stove chimney, and
make the stove hard to start.
There are two kinds of safe chimney: masonry, of brick or concrete block with a fired clay tile
liner, and listed factory-built, consisting of two layers of steel with insulating material in
between. A masonry chimney should be built by a professional mason in compliance with
local codes. A factory-built chimney must be installed according to the manufacturer’s
instructions.
The flue system must be capable of venting the products of combustion. The chimney must
be cleaned and have a correct draft. A professional should make inspection.
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The appliance may be secured to the floor (a hole in stove leg is for this purpose);
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All connections must be effected using rigid materials;
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A gas tap must be put in the pipe near the appliance.
