Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 34·2.44
Flue cleaning requirements
Cleaning openings must allow easy passage of a sweeping brush and be non-combustible (except when fitted to combustible flue pipes), and the entire flue must be sweepable after appliance installation.
Openings for cleaning the flue should allow easy passage of the sweeping brush and be non-combustible except where fitted to a combustible flue pipe, such as a plastic flue pipe. It should be possible to sweep the whole flue after the appliance has been installed.
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