10
MAXIMUM ALLOWABLE EXPOSED VENT LENGTHS INSULATION TABLE -- FT. (M)
Maximum Length of Uninsulated and Insulated Vent Pipe-Ft (M)
Single Stage
Furnace
Input
Winter Design
Temp ° F (° C)
Pipe
Length in
Ft. & M
No Insulation
3/8-in. (9.5 mm) Insulation
1/2-in. (12.7 mm) Insulation
Pipe Diameter-inches (mm)
Pipe Diameter-inches (mm)
Pipe Diameter-inches (mm)
1 1/2
2
2 1/2
3
4
1 1/2
2
2 1/2
3
4
1 1/2
2
2 1/2
3
4
(38)
(51)
(64)
(76) (102) (38)
(51)
(64)
(76)
(102) (38)
(51)
(64)
(76)
(102)
40000
20 (-10)
Ft.
48
42
42
N/A
N/A
50
122
111
N/A
N/A
50
144
130
N/A
N/A
M
14.6
12.8
12.8
N/A
N/A
15.2
37.2
33.8
N/A
N/A
15.2
43.9
39.6
N/A
N/A
0 (-20)
Ft.
25
19
17
N/A
N/A
50
75
66
N/A
N/A
50
90
79
N/A
N/A
M
7.6
5.8
5.2
N/A
N/A
15.2
22.9
20.1
N/A
N/A
15.2
27.4
24.1
N/A
N/A
-20 (-30)
Ft.
14
7
5
N/A
N/A
50
52
45
N/A
N/A
50
64
55
N/A
N/A
M
4.3
2.1
1.5
N/A
N/A
15.2
15.8
13.7
N/A
N/A
15.2
19.5
16.8
N/A
N/A
-40 (-40)
Ft.
7
0
0
N/A
N/A
50
38
31
N/A
N/A
50
48
40
N/A
N/A
M
2.1
0.0
0.0
N/A
N/A
15.2
11.6
9.4
N/A
N/A
15.2
14.6
12.2
N/A
N/A
60000
20 (-10)
Ft.
30
61
61
54
N/A
30
135
163
142
N/A
30
135
191
166
N/A
M
9.1
18.6
18.6
16.5
N/A
9.1
41.1
49.7
43.3
N/A
9.1
41.1
58.2
50.6
N/A
0 (-20)
Ft.
30
31
30
23
N/A
30
113
100
85
N/A
30
135
120
101
N/A
M
9.1
9.4
9.1
7.0
N/A
9.1
34.4
30.5
25.9
N/A
9.1
41.1
36.6
30.8
N/A
-20 (-30)
Ft.
24
17
15
7
N/A
30
81
70
57
N/A
30
98
85
70
N/A
M
7.3
5.2
4.6
2.1
N/A
9.1
24.7
21.3
17.4
N/A
9.1
29.9
25.9
21.3
N/A
-40 (-40)
Ft.
15
8
5
0
N/A
30
61
52
40
N/A
30
75
64
51
N/A
M
4.6
2.4
1.5
0.0
N/A
9.1
18.6
15.8
12.2
N/A
9.1
22.9
19.5
15.5
N/A
80000
20 (-10)
Ft.
20
70
78
70
60
20
70
175
183
154
20
70
175
215
181
M
6.1
21.3
23.8
21.3
18.3
6.1
21.3
53.3
55.8
46.9
6.1
21.3
53.3
65.5
55.2
0 (-20)
Ft.
20
42
41
33
21
20
70
132
111
89
20
70
157
133
107
M
6.1
12.8
12.5
10.1
6.4
6.1
21.3
40.2
33.8
27.1
6.1
21.3
47.9
40.5
32.6
-20 (-30)
Ft.
20
25
23
14
1
20
70
94
77
57
20
70
113
94
71
M
6.1
7.6
7.0
4.3
0.3
6.1
21.3
28.7
23.5
17.4
6.1
21.3
34.4
28.7
21.6
-40 (-40)
Ft.
20
14
12
3
0
20
70
71
56
38
20
70
86
70
50
M
6.1
4.3
3.7
0.9
0.0
6.1
21.3
21.6
17.1
11.6
6.1
21.3
26.2
21.3
15.2
100000
20 (-10)
Ft.
N/A
25
99
89
78
N/A
25
110
233
265
N/A
25
110
235
229
M
N/A
7.6
30.2
27.1
23.8
N/A
7.6
33.5
71.0
80.8
N/A
7.6
33.5
71.6
69.8
0 (-20)
Ft.
N/A
25
55
46
33
N/A
25
110
145
117
N/A
25
110
173
140
M
N/A
7.6
16.8
14.0
10.1
N/A
7.6
33.5
44.2
35.7
N/A
7.6
33.5
52.7
42.7
-20 (-30)
Ft.
N/A
25
34
24
11
N/A
25
110
103
79
N/A
25
110
124
97
M
N/A
7.6
10.4
7.3
3.4
N/A
7.6
33.5
31.4
24.1
N/A
7.6
33.5
37.8
29.6
-40 (-40)
Ft.
N/A
23
20
11
0
N/A
25
95
77
55
N/A
25
110
94
70
M
N/A
7.0
6.1
3.4
0.0
N/A
7.6
29.0
23.5
16.8
N/A
7.6
33.5
28.7
21.3
120000
20 (-10)
Ft.
N/A
N/A
15
99
86
N/A
N/A
15
100
219
N/A
N/A
15
100
250
M
N/A
N/A
4.6
30.2
26.2
N/A
N/A
4.6
30.5
66.8
N/A
N/A
4.6
30.5
76.2
0 (-20)
Ft.
N/A
N/A
15
51
38
N/A
N/A
15
100
130
N/A
N/A
15
100
156
M
N/A
N/A
4.6
15.5
11.6
N/A
N/A
4.6
30.5
39.6
N/A
N/A
4.6
30.5
47.5
-20 (-30)
Ft.
N/A
N/A
15
28
14
N/A
N/A
15
100
88
N/A
N/A
15
100
108
M
N/A
N/A
4.6
8.5
4.3
N/A
N/A
4.6
30.5
26.8
N/A
N/A
4.6
30.5
32.9
-40 (-40)
Ft.
N/A
N/A
15
14
0
N/A
N/A
15
85
62
N/A
N/A
15
100
79
M
N/A
N/A
4.6
4.3
0.0
N/A
N/A
4.6
25.9
18.9
N/A
N/A
4.6
30.5
24.1
140000
20 (-10)
Ft.
N/A
N/A
10
90
99
N/A
N/A
10
90
210
N/A
N/A
10
90
210
M
N/A
N/A
3.0
27.4
30.2
N/A
N/A
3.0
27.4
64.0
N/A
N/A
3.0
27.4
64.0
0 (-20)
Ft.
N/A
N/A
10
61
47
N/A
N/A
10
90
153
N/A
N/A
10
90
183
M
N/A
N/A
3.0
18.6
14.3
N/A
N/A
3.0
27.4
46.6
N/A
N/A
3.0
27.4
55.8
-20 (-30)
Ft.
N/A
N/A
10
35
21
N/A
N/A
10
90
104
N/A
N/A
10
90
128
M
N/A
N/A
3.0
10.7
6.4
N/A
N/A
3.0
27.4
31.7
N/A
N/A
3.0
27.4
39.0
-40 (-40)
Ft.
N/A
N/A
10
20
NA
N/A
N/A
10
90
75
N/A
N/A
10
90
94
M
N/A
N/A
3.0
6.1
NA
N/A
N/A
3.0
27.4
22.9
N/A
N/A
3.0
27.4
28.7
*Not all families have these models.
915SA
