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Radijator Inženjering d.o.o, 36000 Kraljevo, Živojina Lazića - Solunca br.6, Srbija
tel. +381 36 399 140, fax. +381 36 399 150, http://www.radijator.rs
On the smoke pipe, approximately 100mm from the chimney of the boiler, an opening should
be drilled, and install an insert for flue gas temperature probe. Without the flue gas temperature
information, there is no automatic boiler operation mode. The chimney itself should be made of
ceramic pipes, there should be 3 - 5 cm thick insulation around them and the final outer layer is brick
or special chimney elements. If the chimney is not made of ceramics though, but of brick, the surface
of the light section of such a chimney must be 30% larger than this area of the ceramic chimney.
The chimney must also have a cleaning door and they must seal well. The chimney exit on the
roof has to be in accordance with certain regulations. There are two different cases: if the angle of the
roof is smaller than 12⁰ and if the angle of the roof is greater than 12⁰. For an angle smaller than 12⁰,
the height of the chimney above the roof is 1m and for an angle greater than 12⁰. see picture 5.
Picture 5. Height of the chimney
If you think that the chimney is too powerful and that too much cold air flows through the boiler,
at the exit of the boiler there is a flap that can reduce the flow of exhaust gases. The chimney needs
to be cleaned regularly or at least once a year.
If the chimney is not of the correct height, cross-section, or if it is not cleaned, complications in
boiler operation might occur. First of all, a high-temperature mode of operation is not possible, i.e. there
is no maximum operating power, the consequence of this is the occurrence of condensation which affects
the service life of the boiler.
A weak chimney is the main reason for having a smoke on the upper or lower door, especially
at higher fan speeds during the ignition or during operation of the boiler.
If there is too much smoke on the door and in the boiler room during the ignition of the boiler,
or the flue gas temperature does not rise enough for the boiler to start operating and all because of the
insufficiently strong chimney, it is technically justified to remove the wire turbulators from the pipe
exchanger.
