A.O. Smith 200 Instruction Manual page 10

IMPORTANT!
VENT PRESSURE MUST BE MAINTAINED
BETWEEN -0.02" W.C. AND -0.04" W.C. AT 24"
(61.0 cm) ABOVE BOILER COLLAR.
TABLE 7. STANDARD VERTICAL VENTING (CATEGORY I)
APPLIANCE
MODEL CATEGORY
I000
1300
1500
1850
2100
2500
* 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
and .2 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.
STANDARD VENT - VERTICAL (CATEGORY I)
CERTIFIED
VENTING
MATERIAL
TYPE B OR
I
EQUIVALENT
TYPE B OR
I
EQUIVALENT
TYPE B OR
I
EQUIVALENT
TYPE B OR
I
EQUIVALENT
Figure 5.
EXHAUST MAXIMUM LENGTH WITHOUT
VENT SIZE BAROMETRIC DAMPER (FEET)
(INCHES)
10"(25.4 cm) 35 Feet (10.7 m) without damper
*70 Feet (21.3 m) max. with damper
35 Feet (10.7 m) without damper
12" (30.5 cm) *70 Feet (21.3 m) max. with damper
14"(35.6 cm) 35 Feet (10.7 m) without damper
*70 Feet (21.3 m) max. with damper
16" (40.6 cm) 35 Feet (10.7 m) without damper
*70 Feet (21.3 m) max. with damper
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