Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 89·B.7
Temperature classes for chimneys
Chimney temperature classes are designated by 'T' followed by a number indicating the maximum nominal working temperature (average flue gas temperature at rated output), with classes ranging from T080 (80°C) to T600 (600°C).
Temperature classes are set out in Table B1 and expressed as 'T' followed by a number which is less than or equal to the nominal working temperature, i.e. the average flue gas temperature obtained during the nominal/rated output test (usually the maximum operating level).
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