Lennox EL297DFV Series Unit Information page 51

Maximum Allowable Exhaust Vent Length Using Ventilated Attic or Crawl Space For Intake Air in Feet
NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.
Number 1-1/2
Of 90°
Model
Elbows
045 070 090
Used
1 15 10
2 10
3
4
5
n/a
6 n/a
n/a
7
8
9
10
TABLE 23
Standard Termination at Elevation 0 - 10,000 ft
2" Pipe
Model
110 045 070 090
61 46 24
56 41 19
51 36 14
46 31 9
41 26 4
n/a
36 21
31 16
26 11 n/a
21 6
16 1
2-1/2" Pipe
Model
110 045 070
90 90
85 85
80 80
75 75
70 70
n/a
65 65
60 60
55 55
50 50
45 45
Page 51
3" Pipe
Model
090 110 045 070
68 33 108 107
63 28 103 102
58 23 98 97
53 18 93 92
48 13 88 87
43 8 81 82
38 3 78 77
33 73 72
28 n/a 68 67
23 63 62
090 110
88 88
83 83
78 78
73 73
68 68
63 63
58 58
53 53
48 48
43 43