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MFC Series Boiler Vent and Combustion Air Guide
TAG-0080_OG
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GF-148-V
•
3/29/2023
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33
TABLE 7: Altitude Correction
Site Elevation
(feet above sea level)
Altitude Correction Factor
(CF)
0
1
500
0.982
1000
0.964
1500
0.947
2000
0.930
2500
0.913
3000
0.896
3500
0.880
4000
0.864
4500
0.848
5000
0.832
5500
0.817
6000
0.801
6500
0.787
7000
0.772
7500
0.758
8000
0.743
8500
0.729
9000
0.715
9500
0.701
10000
0.688
TABLE 8: Round Duct of Identical Pressure Drop to Rectangular Duct
Adjacent
Side of Duct
(in.)
Side of Rectangular Duct (in.)
6
8
10
12
14
16
18
20
22
24
6
6.6
8
7.6
8.7
10
8.4
9.8
10.9
12
9.1
10.7
12
13.1
14
9.8
11.5
12.9
14.2
15.3
16
10.4
12.2
13.7
15.1
16.4
17.5
18
11
12.9
14.5
16
17.3
18.5
19.7
20
11.5
13.5
15.2
16.8
18.2
19.5
20.7
21.9
22
12
14.1
15.9
17.6
19.1
20.4
21.7
22.9
24
24
12.4
14.6
16.5
18.3
19.9
21.3
22.7
23.9
25.1
26.2
Reference:
1.
National Fuel Gas Code, 2006 edition
, American National Standards Institute, Inc
(ANSI Z223.1-2006) and National Fire Protection Association (NFPA54-2006)
2. CSA B149.1 (For Canada installations)