Allied A96UH1E - Maximum Vent Lengths; Table 5 A. Maximum Allowable Intake or Exhaust Vent Length in Feet; Table 5 B.

508297-01 Page 19 of 57Issue 2219
Maximum Allowable Intake or Exhaust Vent Length in Feet
Standard Termination at Elevation 0 - 2,000 ft
Number
of 90°
Elbows
Used
1-1/2” Pipe 2” Pipe 2-1/2" Pipe 3" Pipe
Capacity Capacity Capacity Capacity
030 045 070 090 110 135
030/
045
070 090 110 135
030/
045
070 090 110 135
030/
045
070 090 110 135
1 25 20 15
n/a n/a n/a
81 66 44 24
n/a
115 115 93 58
n/a
138 137 118 118 80
2 20 15 10 76 61 39 19 110 110 88 53 133 132 113 113 75
3 15 10
n/a
71 56 34 14 105 105 83 48 128 127 108 108 70
4 10
n/a
66 51 29
n/a
100 100 78 43 123 122 103 103 65
5
n/a
61 46 24 95 95 73 38 118 117 98 98 60
6 56 41 19 90 90 68 33 113 112 93 93 55
7 51 36 14 85 85 63 28 108 107 88 88 50
8 46 31
n/a
80 80 58 23 103 102 83 83 45
9 41 26 75 75 53 18 98 97 78 78 40
10 36 21 70 70 48 13 93 92 73 73 35
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.
NOTE - Contact your local FTC if more than 85ft of venting is needed.
Table 5A.
Maximum Allowable Intake or Exhaust Vent Length in Feet
Standard Termination at Elevation 2,001 - 10,000 ft
Number of
90° Elbows
Used
2” Pipe 2-1/2" Pipe 3" Pipe
Capacity Capacity Capacity
030/
045
070 090 110 135
030/
045
070 090 110 135
030/
045
070 090 110 135
1 81 35 20
n/a n/a
115 110 67 53
n/a
138 137 118 118 80
2 76 30 15 110 105 62 48 133 132 113 113 75
3 71 25 10 105 100 57 43 128 127 108 108 70
4 66 20
n/a
100 95 52 38 123 122 103 103 65
5 61 15 95 90 47 33 118 117 98 98 60
6 56 10 90 85 42 28 113 112 93 93 55
7 51
n/a
85 80 37 23 108 107 88 88 50
8 46 80 75 32 18 103 102 83 83 45
9 41 75 70 27 13 98 97 78 78 40
10 36 70 65 22 n/a 93 92 73 73 35
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.
NOTE - Contact your local FTC if more than 85ft of venting is needed.
Table 5B.