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MFC Series Boiler Vent and Combustion Air Guide
TAG-0080_OG
•
GF-148-V
•
3/29/2023
Technical Support
•
(800) 526-0288
•
Mon-Fri, 8 am - 5 pm EST Page 25 of
33
TABLE 5: Ducted Combustion Air Duct Pressure Drop (Eq. Ft.)
for
MFC 5000
MMBTU Boiler
Inlet Duct
& No.
Boilers
Duct Section Type
OUTSIDE AIR TEMPERATURE (°F)
-30 °F
-15 °F
0 °F
20 °F
40 °F
60 °F
80 °F
100
°F
120
°F
1
2"
Duct
Single
Boiler
Straight Run
0.33
0.35
0.37
0.39
0.42
0.45
0.48
0.51
0.54
90° Elbow
2.83
2.97
3.12
3.33
3.55
3.79
4.04
4.31
4.60
45° Elbow
2.19
2.30
2.41
2.57
2.75
2.93
3.13
3.34
3.56
Ent. Loss
6.96
7.31
7.67
8.18
8.73
9.31
9.93
10.60
11.31
14"
Duct
Single
Boiler
Straight Run
0.15
0.16
0.17
0.18
0.19
0.21
0.22
0.23
0.25
90° Elbow
1.42
1.49
1.56
1.67
1.78
1.90
2.02
2.16
2.30
45° Elbow
1.10
1.16
1.22
1.30
1.38
1.48
1.58
1.68
1.79
Ent. Loss
3.76
3.94
4.14
4.41
4.71
5.02
5.36
5.72
6.10
16"
Duct
Two
Boilers
Straight Run
0.29
0.31
0.32
0.34
0.37
0.39
0.42
0.45
0.47
90° Elbow
3.14
3.29
3.45
3.68
3.93
4.19
4.47
4.77
5.09
45° Elbow
2.45
2.57
2.69
2.87
3.06
3.27
3.49
3.72
3.97
Ent. Loss
8.81
9.25
9.70
10.35
11.04
11.78
12.5
7
13.41
14.31
16"
Duct
Two
Boilers
Straight Run
0.16
0.17
0.18
0.19
0.20
0.22
0.23
0.25
0.26
90° Elbow
1.86
1.95
2.05
2.19
2.33
2.49
2.65
2.83
3.02
45° Elbow
1.45
1.52
1.60
1.71
1.82
1.94
2.07
2.21
2.36
Ent. Loss
5.50
5.77
6.06
6.46
6.89
7.36
7.85
8.37
8.93
18"
Duct
Three
Boilers
Straight Run
0.35
0.37
0.39
0.41
0.44
0.47
0.50
0.53
0.57
90° Elbow
4.19
4.39
4.61
4.92
5.24
5.60
5.97
6.37
6.80
45° Elbow
3.27
3.43
3.60
3.84
4.09
4.37
4.66
4.97
5.30
Ent. Loss
12.38
12.99
13.6
3
14.54
15.51
16.55
17.6
6
18.84
20.10
20"
Duct
Three
Boilers
Straight Run
0.21
0.22
0.23
0.24
0.26
0.28
0.30
0.31
0.34
90° Elbow
2.62
2.75
2.89
3.08
3.29
3.51
3.74
3.99
4.26
45° Elbow
2.05
2.15
2.25
2.40
2.56
2.74
2.92
3.11
3.32
Ent. Loss
8.12
8.52
8.94
9.54
10.18
10.86
11.5
8
12.36
13.19
20"
Duct
Four
Boilers
Straight Run
0.36
0.38
0.40
0.42
0.45
0.48
0.51
0.55
0.58
90° Elbow
4.66
4.89
5.14
5.48
5.84
6.23
6.65
7.10
7.57
45° Elbow
3.64
3.82
4.01
4.27
4.56
4.86
5.19
5.54
5.91
Ent. Loss
14.44
15.15
15.9
0
16.96
18.09
19.30
20.5
9
21.97
23.44
22"
Duct
Four
Boilers
Straight Run
0.22
0.23
0.24
0.26
0.28
0.30
0.32
0.34
0.36
90° Elbow
3.05
3.20
3.36
3.58
3.82
4.08
4.35
4.64
4.95
45° Elbow
2.38
2.49
2.62
2.79
2.98
3.18
3.39
3.61
3.86
Ent. Loss
9.86
10.35
10.8
6
11.58
12.36
13.18
14.0
7
15.01
16.01