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TABLE 14
Maximum Allowable Vent Length in Feet
NOTE - 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.
Standard Termination at Elevation 0 - 4500 ft
Number Of
90° Elbows
Used
2” Pipe
2-1/2” Pipe
3” Pipe
Model
Model
Model
045
070
090
110
135
045
070
090
110
135
045
070
090
110
135
1
81
66
44
24
n/a
115
115
93
58
n/a
138
137
118
118
114
2
76
61
39
19
110
110
88
53
133
132
113
113
109
3
71
56
34
14
105
105
83
48
128
127
108
108
104
4
66
51
29
n/a
100
100
78
43
123
122
103
103
99
5
61
46
24
95
95
73
38
118
117
98
98
94
6
56
41
19
90
90
68
33
113
112
93
93
89
7
51
36
14
85
85
63
28
108
107
88
88
84
8
46
31
n/a
80
80
58
23
103
102
83
83
79
9
41
26
75
75
53
18
98
97
78
78
74
10
36
21
70
70
48
13
93
92
73
73
69
Standard Termination Elevation 4500 - 10,000 ft
Number Of
90° Elbows
Used
2” Pipe
2-1/2” Pipe
3” Pipe
Model
Model
Model
045
070
090
110
135
045
070
090
110
135
045
070
090
110
135
1
81
66
44
n/a
n/a
115
115
93
58
n/a
138
137
118
118
114
2
76
61
39
110
110
88
53
133
132
113
113
109
3
71
56
34
105
105
83
48
128
127
108
108
104
4
66
51
29
100
100
78
43
123
122
103
103
99
5
61
46
24
95
95
73
38
118
117
98
98
94
6
56
41
19
90
90
68
33
113
112
93
93
89
7
51
36
14
85
85
63
28
108
107
88
88
84
8
46
31
n/a
80
80
58
23
103
102
83
83
79
9
41
26
75
75
53
18
98
97
78
78
74
10
36
21
70
70
48
13
93
92
73
73
69
