VENTING
C.VENT PIPING AND CHIMNEY
1.Install vent piping in accordance with Venting of Equipment part of the National Fuel Gas Code, ANSI Z223.1/NFPA 54, sections 7.2, 7.3 or 7.4 of CAN/CSA B149.1, Natural Gas and Propane Installation Code, or applicable provisions of the local building codes.
2.Inspect the existing chimney and lining for structural soundness, corrosion and perforations. Repair as necessary.
3.Install vent pipe to slope upward at least 1/4” per lineal foot (21 mm per meter) between the draft hood outlet and the chimney.
Figure 4.2: Venting with Vent Damper in Vertical Position
4.Before connection of joints, inspect the vent pipe interior for foreign objects such as tools, equipment, rags, etc. and remove if present.
5.Insert vent pipe into but not beyond the inside wall of the chimney flue.
6.Do not connect vent connectors serving appliances vented by natural draft into any portion of mechanical draft systems operating under positive pressure.
7.Support horizontal portions of the venting system to prevent sagging by use of metal strapping or equivalent means. Locate supports at no more than 4 foot (1.2 meter) intervals.
Figure 4.3: Venting with Vent Damper in Horizontal Position
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