Allied Air A96US2V Installation Instructions Manual page 21

Maximum Allowable Exhaust Vent Lengths with Furnace Installed in a Closet or Basement Using Ventilated
Number
of 90°
Elbows
45
Used
1 66
2 61
3 56
4 51
5 46
6 41
7 36
8 31
9 26
10 21
Number
of 90°
Elbows
45
Used
1 66
2 61
3 56
4 51
5 46
6 41
7 36
8 31
9 26
10 21
* 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.
* Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.
507404-04
Attic or Crawl Space for Intake Air in Feet
Standard Termination at Elevation 0 - 4500 ft
2" Pipe
Model
70 90 110 135
51 29 9 n/a
46 24 4
41 19 n/a
36 14
31 9
26 4
21 n/a
16
11
6
Standard Termination at Elevation 4500 - 10,000 ft
2" Pipe
Model
70 90 110 135
51 29 n/a n/a
46 24
41 19
36 14
31 9
26 4
21 n/a
16
11
6
2-1/2" Pipe
Model
45 70 90 110
95 95 73 38
90 90 68 33
85 85 63 28
80 80 58 23
75 75 53 18
70 70 48 13
65 65 43 8
60 60 38 3
55 55 33 n/a
50 50 28
2-1/2" Pipe
Model
45 70 90 110
95 95 73 38
90 90 68 33
85 85 63 28
80 80 58 23
75 75 53 18
70 70 48 13
65 65 43 8
60 60 38 3
55 55 33 n/a
50 50 28
Table 5C
Issue 1621
3" Pipe
Model
135 45 70 90
n/a 113 112 93
108 107 88
103 102 83
98 97 78
93 92 73
88 87 68
83 82 63
78 77 58
73 72 53
68 67 48
3" Pipe
Model
135 45 70 90
n/a 113 112 93
108 107 88
103 102 83
98 97 78
93 92 73
88 87 68
83 82 63
78 77 58
73 72 53
68 67 48
110 135
93 89
88 84
83 79
78 74
73 69
68 64
63 59
58 54
53 49
48 44
110 135
93 89
88 84
83 79
78 74
73 69
68 64
63 59
58 54
53 49
48 44
Page 21 of 80