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Bryan Steam, LLC
www.bryanboilers.com
Phone: 765-473-6651
783 N Chili Ave, Peru, IN 46970 [email protected]
Combined pressure drop through Combustion duct shall not exceed 100 equivalent feet (30.84 meters).
Table 7: Combustion Air Pressure Drop Data
Flue Vent Diameter
in. (mm)
Straight Length Equivalent
ft/ft (m/m)
90° Elbow Equivalent
ft/ft (m/m)
45° Elbow Equivalent
ft/ft (m/m)
Velocity
(fpm)
Free Flex 1000 Pressure Drop in Equivalent Feet (Meters)
6 (160)
0.6 (0.182)
6.25 (1.905)
3.13 (0.954)
1121
8 (200)
0.13 (0.039)
1.32 (0.402)
0.658 (0.2)
631
Free Flex 1500 Pressure Drop in Equivalent Feet (Meters)
8 (200)
0.3 (0.091)
3.03 (0.923)
1.49 (0.045)
946
10 (250)
0.09 (0.027)
0.92 (0.28)
0.46 (0.14)
605
Free Flex 2000 Pressure Drop in Equivalent Feet (Meters)
8 (200)
0.53 (0.161)
5.26 (1.603)
2.63 (0.801)
1264
10 (250)
0.164 (0.049)
1.64 (0.499)
0.82 (0.249)
809
12 (315)
0.063 (0.019)
0.63 (0.192)
0.314 (0.095)
562
Free Flex 2500 Pressure Drop in Equivalent Feet (Meters)
8 (200)
0.83 (0.0250)
8.3 (2.529)
4.17 (1.271)
1576
10 (250)
0.26 (0.079)
2.56 (0.78)
1.28 (0.39)
1009
12 (315)
0.1 (0.03)
0.98 (0.298)
0.49 (0.149)
701
Free Flex 3000 Pressure Drop in Equivalent Feet (Meters)
8 (200)
1.19 (0.362)
12.5 (3.81)
5.9 (1.798)
1895
10 (250)
0.37 (0.112)
3.7 (1.127)
1.85 (0.563)
1213
12 (315)
0.14 (0.042)
1.41 (0.429)
0.7 (0.213)
842
Free Flex 3500 Pressure Drop in Equivalent Feet (Meters)
10 (250)
0.39 (0.118)
3.92 (1.194)
1.96 (0.597)
1414
12 (315)
0.15 (0.045)
1.49 (0.454)
0.75 (0.228)
982
14 (356)
0.07 (0.021)
0.67 (0.204)
0.33 (0.1)
722
Free Flex 4000 Pressure Drop in Equivalent Feet (Meters)
10 (250)
0.51 (0.155)
5.13 (1.563)
2.56 (0.78)
1616
12 (315)
0.2 (0.06)
1.96 (0.597)
0.97 (0.295)
1122
14 (356)
0.087 (0.026)
0.87 (0.265)
0.44 (0.134)
825
Free Flex 4500 Pressure Drop in Equivalent Feet (Meters)
12 (315)
0.25 (0.076)
2.5 (0.762)
1.23 (0.374)
1264
14 (356)
0.11 (0.033)
1.1 (0.335)
0.55 (0.167)
928
16 (406)
0.054 (0.016)
0.55 (0.167)
0.27 (0.082)
711
Free Flex 5000 Pressure Drop in Equivalent Feet (Meters)
12 (315)
0.31 (0.094)
3.13 (0.954)
1.54 (0.469)
1403
14 (356)
0.14 (0.042)
1.35 (0.411)
0.68 (0.207)
1030
16 (406)
0.067 (0.02)
0.67 (0.204)
0.34 (0.103)
789
Free Flex 5500 Pressure Drop in Equivalent Feet (Meters)
12 (315)
0.37 (0.112)
3.7 (1.127)
1.85 (0.563)
1544
14 (356)
0.17 (0.051)
1.64 (0.499)
0.82 (0.249)
1134
16 (406)
0.082 (0.024)
0.81 (0.246)
0.41 (0.124)
868
Free Flex 6000 Pressure Drop in Equivalent Feet (Meters)
12 (315)
0.44 (0.134)
4.55 (1.386)
2.22 (0.676)
1684
14 (356)
0.2 (0.06)
1.96 (0.597)
0.98 (0.298)
1237
16 (406)
0.097 (0.295)
0.97 (0.295)
0.49 (0.149)
947