503.3.3 Mechanical draft systems.
FGC § 503.3.3
Mechanical draft systems shall comply with the following: 1. Mechanical draft systems shall be listed and shall be installed in accordance with the terms of their listing and both the appliance and the mechanical draft system manufacturer's instructions.
2.Appliances requiring venting shall be permitted to be vented by means of mechanical draft systems of either forced or induced draft design.
3.Forced draft systems and all portions of induced draft systems under positive pressure during operation shall be designed and installed so as to prevent leakage of flue or vent gases into a building.
4.Vent connectors serving appliances vented by natural draft shall not be connected into any portion of mechanical draft systems operating under positive pressure.
5.Where a mechanical draft system is employed, provisions shall be made to prevent the flow of gas to the main burners when the draft system is not performing so as to satisfy the operating requirements of the appliance for safe performance.
6.The exit terminals of mechanical draft systems shall be not less than 7 feet (2133.6 mm) above finished ground level where located adjacent to public walkways and shall be located as specified in Section 503.8, Items 1 and 2.
