18-28-803.9 Chimney connector construction.

   Chimney connectors for low-heat appliances shall be made of sheet steel pipe that is resistant to corrosion and heat not less than that required for galvanized steel as specified in Table 18-28-803.9(1). Connectors for medium-heat appliances and high-heat appliances shall be of sheet steel not less than the thickness specified in Table 18-28-803.9(2).

Table 18-28-803.9(1)
Minimum Chimney Connector Thickness for Low- Heat Appliances

 

Diameter of Connector (inches)	Minimum Nominal Thickness (Galvanized) (inches)
5 and smaller	0.022 (No. 26 Gauge)
Larger than 5 and up to 10	0.028 (No. 24 Gauge)
Larger than 10 and up to 16	0.034 (No. 22 Gauge)
Larger than 16	0.064 (No. 16 Gauge)

 

For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm 2 .

Table 18-28-803.9(2)
Minimum Chimney Connector Thickness for Medium- and High-Heat Appliances

 

Area (square inches)	Equivalent Round Diameter (inches)	Minimum Nominal Thickness (inches)
0 – 154	0 – 14	0.060 (No. 16 Gauge)
155 – 201	15 – 16	0.075 (No. 14 Gauge)
202 – 254	17 – 18	0.105 (No. 12 Gauge)
Greater than 254	Greater than 18	0.135 (No. 10 Gauge)

 

For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm 2 .