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31-5000726 Rev. 0
Maximum Allowable Intake or Exhaust Vent Length in Feet
Concentric Termination at Elevation 0 - 4,500 ft
Number
of 90°
Elbows
Used
1-1/2" Pipe
2" Pipe
2-1/2" Pipe
3" Pipe
Model
Model
Model
Model
45
70
90 110 135 45
70
90 110 135 45
70
90 110 135 45
70
90 110 135
1
25
20
n/a n/a n/a
68
53
37
17
n/a
100 100 84
49
n/a
116 116 109 109 100
2
20
15
63
48
32
12
95
95
79
44
111 111 104 104 95
3
15
10
58
43
27
7
90
90
74
39
106 106 99
99
90
4
10
n/a
53
38
22
n/a
85
85
69
34
101 101 94
94
85
5
n/a
48
33
17
80
80
64
29
96
96
89
89
80
6
43
28
12
75
75
59
24
91
91
84
84
75
7
38
23
7
70
70
54
19
86
86
79
79
70
8
33
18
n/a
65
65
49
14
81
81
74
74
65
9
28
13
60
60
44
9
76
76
69
69
60
10
23
8
55
55
39
n/a
71
71
64
64
55
Concentric Termination Elevation 4,501 - 10,000 ft
Number
of 90°
Elbows
Used
1-1/2" Pipe
2" Pipe
2-1/2" Pipe
3" Pipe
Model
Model
Model
Model
45
70
90 110 135 45
70
90 110 135 45
70
90 110 135 45
70
90 110 135
1
25
20
n/a n/a n/a
68
53
37
n/a n/a
100 100 84
49
n/a
116 116 109 109 100
2
20
15
63
48
32
95
95
79
44
111 111 104 104 95
3
15
10
58
43
27
90
90
74
39
106 106 99
99
90
4
10
n/a
53
38
22
85
85
69
34
101 101 94
94
85
5
n/a
48
33
17
80
80
64
29
96
96
89
89
80
6
43
28
12
75
75
59
24
91
91
84
84
75
7
38
23
7
70
70
54
19
86
86
79
79
70
8
33
18
n/a
65
65
49
14
81
81
74
74
65
9
28
13
60
60
44
9
76
76
69
69
60
10
23
8
55
55
39
n/a
71
71
64
64
55
*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.
Table 10B.