Lennox MERIT Series Installation Instructions Manual page 17

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 calcu-
lation.
1-1/2" Pipe
No.Of
90° Model
Elbows
045 070
1 15 15
2 10 10
3
4
5
6
n/a n/a
7
8
9
10
1-1/2" Pipe
No. Of
90° Model
Elbows
045 070
1 15 15
2 10 10
3
4
5
6
n/a n/a
7
8
9
10
Standard Termination at Elevation 0 - 4500 ft
2" Pipe
Model
090 110 045 070
81 66
76 61
71 56
66 51
61 46
n/a n/a
56 41
51 36
46 31
41 26
36 21
Standard Termination Elevation 4500 - 10,000 ft
2" Pipe
Model
090 110 045 070
81 66
76 61
71 56
66 51
61 46
n/a n/a
56 41
51 36
46 31
41 26
36 21
TABLE 7
2-1/2" Pipe
Model
090 110 045 070
44 4 115 115
39 9 110 110
34 105 105
29 100 100
24 95 95
19 90 90
n/a
14 85 85
80 80
n/a 75 75
70 70
2-1/2" Pipe
Model
090 110 045 070
44 115 115
39 110 110
34 105 105
29 100 100
24 95 95
n/a
19 90 90
14 85 85
80 80
n/a 75 75
70 70
Page 17
3" Pipe
Model
090 110 045 070
93 48 138 137
88 43 133 132
83 38 128 127
78 33 123 122
73 28 118 117
68 23 113 112
63 18 108 107
58 13 103 102
53 n/a 98 97
48 93 92
3" Pipe
Model
090 110 045 070
93 48 138 137
88 43 133 132
83 38 128 127
78 33 123 122
73 28 118 117
68 23 113 112
63 18 108 107
58 13 103 102
53 98 97
n/a
48 93 92
090 110
118 108
113 103
108 98
103 93
98 88
93 83
88 78
83 73
78 68
73 63
090 110
118 108
113 103
108 98
103 93
98 88
93 83
88 78
83 73
78 68
73 63