A.O. Smith 400, 402, 401, 403 Standard Vent Vertical Category, Type B or, Equivalent, 16 40.6 cm

STANDARD VENT - VERTICAL (CATEGORY I)

IMPORTANT!

VENT PRESSURE MUST BE MAINTAINED BETWEEN -0.02" W.C. AND -0.04" W.C. AT 24" (61.0 cm) ABOVE BOILER COLLAR.

Figure 6.

TABLE 10. STANDARD VERTICAL VENTING (CATEGORY I)

	APPLIANCE	CERTIFIED	EXHAUST	MAXIMUM LENGTH
MODEL	CATEGORY	VENTING	VENT SIZE	WITHOUT BAROMETRIC DAMPER
		MATERIAL	INCHES (cm)	FEET (m)
I000	I	TYPE B OR	10”(25.4 cm)	35 Feet (10.7 m) without damper
		EQUIVALENT		*70 Feet (21.3 m) max. with damper
1300	I	TYPE B OR		35 Feet (10.7 m) without damper
1500		EQUIVALENT	12" (30.5 cm)	*70 Feet (21.3 m) max. with damper
1850	I	TYPE B OR	14"(35.6 cm)	35 Feet (10.7 m) without damper
2100		EQUIVALENT		*70 Feet (21.3 m) max. with damper
2500	I	TYPE B OR	16" (40.6 cm)	35 Feet (10.7 m) without damper
		EQUIVALENT		*70 Feet (21.3 m) max. with damper

*Extending venting over 70 feet (21.3 m) may require special considerations.

•Connection for the appliance exhaust vent to the stack must be as direct as possible. Maximum and minimum venting length for Category I appliances shall be determined per the latest edition of the National Fuel Code (U.S.) and CAN/CSA-B149.1 Installation Code (Canada).

•The horizontal breaching of a vent must have an upward slope of not less than 1/4 inch per linear foot (2 cm/m) from the boiler to the vent terminal. The horizontal portion of the vent shall be supported to maintain clearances and to prevent physical damage or separation of joints.

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