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TABLE 8 Cont.
Maximum Allowable Intake or Exhaust Vent Length in Feet
*Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total. Both Intake and Exhaust must be same pipe size.
NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation
Concentric Termination 0 - 7501”
Number
of 90
Elbows
Used
1-1/2” Pipe 2” Pipe 2-1/2” Pipe 3” Pipe
Model Model Model Model
070 090 110 135 070 090 110 135 070 090 110 135 070 090 110 135
1
15
N/A N/A N/A
83 67 12
N/A
130 89 39
N/A
146 139 114 105
2
10 78 62 7 125 84 34 141 134 109 100
3
N/A
73 57
N/A
120 79 29 136 129 104 95
4
68 52 115 74 24 131 124 99 90
5
63 47 110 69 19 126 119 94 85
6
58 42 105 64 14 121 114 89 80
7
53 37 100 59
N/A
116 109 84 75
8
48 32 95 54 111 104 79 70
9
43 27 90 49 106 99 74 65
10
38 22 85 44 101 94 69 60
Concentric Termination 7501” - 10,000”
Number
of 90
Elbows
Used
1-1/2” Pipe 2” pipe 2-1/2” Pipe 3” Pipe
Model Model Model Model
070 090 110 135 070 090 110 135 070 090 110 135 070 090 110 135
1
10
N/A N/A N/A
58 42
N/A N/A
105 64
N/A N/A
121 114 89 80
2
N/A
53 37 100 59 116 109 84 75
3
48 32 95 54 111 104 79 70
4
43 27 90 49 106 99 74 65
5
38 22 85 44 101 94 69 60
6
33 17 80 39 96 89 64 55
7
28 12 75 34 91 84 59 50
8
23
N/A
70 29 86 79 54 45
9
18 65 24 81 74 49 40
10
13 60 19 76 69 44 35