VENTING
Figure 4.4: Direct Exhaust; Sidewall Venting
D. DIRECT EXHAUST; VERTICAL VENTING
1.This vent system will operate with a positive pressure in the vent pipe. Follow vent pipe manufacturer’s instructions for proper assembly of vent pipe and fittings.
2.Refer to Table 4.2 for minimum and maximum vent length allowed.
3.Maintain a minimum 2” (51 mm) clearance between vent pipe and combustible construction.
4.Follow instructions under section C. DIRECT EXHAUST; HORIZONTAL VENTING items 6b through 6h.
5.Horizontal portions of the vent pipe shall slope up not less than 1/4” per foot (21 mm per meter) from the boiler to the vertical vent.
6.Provide a horizontal drain tee in the horizontal vent run. Use silicone drain hose with a 3” (76 mm) diameter loop trap with a water seal. Pipe to drain per local codes.
7.Refer to vent pipe manufacturer’s instructions under vertical venting section for recommendation for penetration through floors and roofs.
8.Vent must terminate 12” (305 mm) above expected snow lines.
9.See Figure 4.5 for details.
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