Section R1003.14, Flue area (appliance), is hereby deleted in its entirety and the following provisions shall be substituted therefor:

Chimney flues shall not be smaller in area than that of the area of the connector from the appliance [see Tables R1003.14(1) and R1003.14(2)]. The sizing of a chimney flue to which multiple appliance venting systems are connected shall be in accordance with the currently adopted edition of the Uniform Mechanical Code.