VENTING
The vent system must terminate so that proper clearances are maintained as cited in local codes or the current edition of the National Fuel Gas Code, ANSI Z223.1/NFPA 54, 7.3.4e and 7.8a,b, as follows:
1.The exit terminals of a mechanical vent system shall be not less than 7 feet (2.13 m) above grade when located adjacent to public walkways, see Figure 23.
2.A venting system shall terminate at least 3 feet (91 cm) above any forced air inlet located within 10 feet (3.1 m), see Figure 23.
3.The venting system shall terminate at least 4 feet (1.2 m) below, 4 feet (1.2 m) horizontally from or, 12 in. (30 cm) above any door, window or gravity air inlet into any building.
The manufacturer also recommends that the vent termination should not be installed closer than 3 feet (91 cm) from an inside corner of an L shaped structure and not be less than 12 in. (30 cm) above grade.
The vent shall terminate a minimum of 12’’ (30.5 cm) above expected snowfall level to prevent blockage of vent termination, see Figure 23.
4.In cold climates, it is recommended that vent termination not be mounted directly above or within 3 feet (91 cm) horizontally from an oil tank vent or gas meter to avoid potential
Plan the vent system layout so that proper clearances are maintained from plumbing and wiring.
Vent pipes serving power vented appliances are classified by building codes as “vent connectors”. Required clearances from combustible materials must be provided in accordance with information in this manual under FACTS TO CONSIDER ABOUT THE LOCATION and VENT TERMINAL INSTALLATIONS, and with the National Fuel Gas Code and local codes.
VENT TERMINAL INSTALLATION
1.After the point of termination has been determined, use the cover plate as a template to mark the hole for the vent pipe to insert through the wall. BEWARE OF CONCEALED WIRING AND PIPING INSIDE OF WALL.
2.If the Vent Terminal is being installed on the outside of a finished wall, it may be easier to mark both the inside and outside wall. Align the holes by drilling a hole through the center of the template from the inside through to the outside. The template can now be positioned on the outside wall using the drilled hole as a centering point for the template.
3.A) MASONRY SIDE WALLS
Chisel an opening approximately one half inch larger than the marked circle.
B) WOODEN SIDE WALLS
Drill a pilot hole approximately one quarter inch outside of the marked circle. This pilot hole is used as a starting point for a
4.When the vent piping cannot pass through an outside wall at a height greater than or equal to 12” above the ground (or above snow accumulation level), then the installation can be modified as shown below.
FIGURE 22.
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