(1) Except as required in Article 9.21.2.1., two or more fuel-burning appliances are permitted to be connected to the same chimney flue provided adequate draft is maintained for the connected appliances and the connections are made as described in Sentences (2) and (3).
(2) Where two or more solid fuel-burning appliances are connected to the same chimney flue, the appliances must be located on the same storey.
(3) The connection referred to in Sentence (2) for a solid fuel-burning appliance shall be made below connections for appliances burning other fuels.