Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 76·5.21
Lining requirements for flues in chimneys with high temperature flue gas (>250°C)
Where flue gas temperature is expected to exceed 250°C, the liner must meet specific provisions including flexible stainless steel liners to BS EN 1858, or other approved materials.
Where the flue gas temperature is expected to be greater than 250ºC the liner should be –
(a) as per the provisions in paragraph 2.22;
(b) as per the provisions in paragraph 3.20; or
(c) a flexible stainless steel liner designated in accordance with BS EN 1858.
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