COMBUSTION- -AIR AND VENT PIPING FOR DIRECT VENT/2- -PIPE (ALL SIZES) AND
NON- -DIRECT VENT/1- -PIPE (SIZES 040 THROUGH 120 ONLY) APPLICATIONS (CON'T.)
ALTITUDE
UNIT SIZE
(BTUH)
FT (M)
40,000
60,000
80,000
5001 to 6000‡
(1524 to 1829)
100,000
120,000
ALTITUDE
UNIT SIZE
(BTUH)
FT (M)
40,000
60,000
6001 to 7000‡
80,000
(1829 to 2134)
100,000
120,000
See notes at end of table.
DIRECT VENT (2-PIPE) ONLY
TERMINATION
PIPE DIA
TYPE
IN. (mm)*
1-1/2 (38)
2 Pipe or 2-in
Concentric
2 (51)
1-1/2 (38)
2 Pipe or 2-in
Concentric
2 (51)
2 (51)
2 Pipe or 2-in
Concentric
2-1/2 (64)
2-1/2 (64)
2 Pipe or 3-in
Concentric
3 (76)
3 (76)†
no disk
2 Pipe or 3-in.
NA
Concentric
4 (102)† no
disk
DIRECT VENT (2-PIPE) ONLY
TERMINATION
PIPE DIA
TYPE
IN. (mm)*
1-1/2 (38)
2 Pipe or 2-in
Concentric
2 (51)
1-1/2 (38)
2 Pipe or 2-in
Concentric
2 (51)
2 (51)
2 Pipe or 2-in
Concentric
2-1/2 (64)
2-1/2 (64)
2 Pipe or 3-in
Concentric
3 (76)
3 (76)†
no disk
2 Pipe or 3-in.
Concentric
NA
NON-DIRECT
VENT (1-PIPE)
NUMBER OF 90° ELBOWS
ONLY
PIPE DIA
1
2
IN. (mm)*
57
52
1-1/2 (38)
(17.4)
(15.8)
70
70
2 (51)
(21.3)
(21.3)
14
9
1-1/2 (38)
(4.3)
(2.7)
60
55
2 (51)
(18.3)
(16.8)
41
36
2 (51)
(12.5)
(11.0)
70
70
2-1/2 (64)
(21.3)
(21.3)
29
21
2-1/2 (64)
(8.8)
(6.4)
70
67
3 (76)
(21.3)
(20.4)
42
35
NA
(12.8)
(10.7)
53
52
3 (76)†
(16.2)
(15.8)
70
70
4 (102)† no disk
(21.3)
(21.3)
NON-DIRECT
VENT (1-PIPE)
NUMBER OF 90° ELBOWS
ONLY
PIPE DIA
1
2
IN. (mm)*
53
48
1-1/2 (38)
(16.2)
(14.6)
70
70
2 (51)
(21.3)
(21.3)
13
8
1-1/2 (38)
(4.0)
(2.4)
57
52
2 (51)
(17.4)
(15.8)
38
33
2 (51)
(11.6)
(10.1)
70
70
2-1/2 (64)
(21.3)
(21.3)
27
19
2-1/2 (64)
(8.2)
(5.8)
68
63
3 (76)
(20.7)
(19.2)
31
24
NA
(9.4)
(7.3)
49
48
3 (76)†
(14.9)
(14.6)
15
3
4
5
6
47
42
40
35
(14.3)
(12.8)
(12.2)
(10.7)
70
70
70
70
(21.3)
(21.3)
(21.3)
(21.3)
NA
NA
NA
NA
54
49
48
47
(16.5)
(14.9)
(14.6)
(14.3)
23
18
17
8
(7.0)
(5.5)
(5.2)
(2.4)
70
70
70
70
(21.3)
(21.3)
(21.3)
(21.3)
12
11
NA
NA
(3.7)
(3.4)
62
57
52
47
(18.9)
(17.4)
(15.8)
(14.3)
29
22
15
9
(8.8)
(6.7)
(4.6)
(2.7)
50
49
48
47
(15.2)
(14.9)
(14.6)
(14.3)
70
70
70
70
(21.3)
(21.3)
(21.3)
(21.3)
3
4
5
6
43
38
37
32
(13.1
(11.6)
(11.3)
(9.8)
68
67
66
64
(20.7)
(20.4)
(20.1)
(19.5)
NA
NA
NA
NA
50
45
44
43
(15.2)
(13.7)
(13.4)
(13.1)
21
16
15
6
(6.4)
(4.9)
(4.6)
(1.8)
68
67
66
64
(20.7)
(20.4)
(20.1)
(19.5)
10
9
NA
NA
(3.0)
(2.7)
58
53
48
43
(17.7)
(16.2)
(14.6)
(13.1)
18
11
NA
NA
(5.5)
(3.4)
47
45
44
43
(14.3)
(13.7)
(13.4)
(13.1)