HP 422690 I Installer's Information Manual page 8

Table 1. Maximum Pipe Length--Direct Vent
ALTITUDE FURNACE
INPUT
54,000
72,000
72,000
0'-1000' 90,000
90,000
108,000
126,000
54,000
72,000
72,000
1001'-2000' 90,000
90,000
108,000
126,000
54,000
72,000
72,000
2001'-3000' 90,000
90,000
108,000
126,000
54,000
72,000
72,000
3001'-4000' 90,000
90,000
108,000
126,000
126,000
54,000
72,000
72,000
4001'-5000' 90,000
108,000
108,000
126,000
54,000
72,000
72,000
5001'-6000' 90,000
108,000
108,000
126,000
54,000
72,000
72,000
6001'-7000' 90,000
108,000
126,000
54,000
72,000
72,000
7001'-8000' 90,000
108,000
126,000
54,000
72,000
72,000
8001'-9000' 90,000
108,000
126,000
54,000
72,000
72,000
9001'-10000' 90,000
108,000
126,000
NOTE 1: The table assumes the use of sweep elbows. If using hard 90 elbows , the vent length should be decreased an
additional 3 feet for every elbow used.
NOTE 2: The shaded portions of the table require the high altitude pressure switch in order to operate the furnace at the listed
vent lengths.
Page 8
ALLOWABLE PIPE LENGTH (feet of each pipe)
PIPE NUMBER OF SWEEP ELBOWS (each pipe)
DIA. 1 2
2" 40 40
2" 40 40
3" 40 40
2" 30 26
3" 40 40
3" 40 40
3" 40 40
2" 40 40
2" 40 37
3" 40 40
2" 25 22
3" 40 40
3" 40 40
3" 40 38
2" 40 40
2" 35 33
3" 40 40
2" 22 19
3" 40 40
3" 40 40
3" 35 30
2" 40 40
2" 30 28
3" 40 40
2" 15 13
3" 40 40
3" 40 40
3" 30 25
3" 40 40
2" 40 40
2" 26 22
3" 40 40
3" 40 40
3" 40 40
3" 40 40
3" 40 40
2" 40 40
2" 21 18
3" 40 40
3" 40 40
3" 40 35
3" 40 40
3" 40 40
2" 40 40
2" 40 40
3" 40 40
3" 40 40
3" 40 40
3" 40 40
2" 40 40
2" 40 40
3" 40 40
3" 40 40
3" 40 40
3" 40 40
2" 40 40
2" 40 40
3" 40 40
3" 40 40
3" 40 40
3" 40 40
2" 40 40
2" 40 37
3" 40 40
3" 40 40
3" 40 40
3" 40 35
3 4 5
40 40 40
37 33 30
40 40 40
22 19 15
40 40 40
40 40 40
40 40 35
40 40 40
33 29 25
40 40 40
19 16 12
40 40 40
40 40 40
33 28 22
40 40 40
29 25 21
40 40 40
16 14 -
40 40 40
40 40 40
25 20 15
40 40 40
26 24 22
40 40 40
11 - -
40 40 40
40 40 40
20 15 10
40 40 35
40 40 40
17 14 12
40 40 40
40 40 40
40 35 30
40 40 40
40 40 35
40 40 40
14 11 -
40 40 40
40 40 40
30 25 20
40 40 40
40 40 35
40 40 40
40 40 36
40 40 40
40 40 40
40 40 40
40 40 35
40 40 40
40 37 35
40 40 40
40 40 40
40 40 40
40 40 35
40 40 40
37 34 31
40 40 40
40 40 40
40 40 40
40 35 30
40 40 40
35 31 27
40 40 40
40 40 40
40 40 40
30 25 20
(SEE NOTE 1)
6 7 8
40 40 40
27 23 20
40 40 40
11 - -
40 40 40
40 40 40
30 25 20
40 40 40
21 19 15
40 40 40
- - -
40 40 40
40 40 40
16 11 -
40 40 40
17 13 -
40 40 40
- - -
40 40 40
40 40 40
10 - -
40 40 40
20 18 17
40 40 40
- - -
40 40 40
40 40 40
- - -
30 25 20 See Note 2 below.
40 40 40
- - -
40 40 40
40 40 40
25 20 15
40 40 40 See Note 2 below.
30 25 20
40 40 40
- - -
40 40 40
40 40 40
15 10 -
40 40 40 See Note 2 below.
30 25 20
40 40 40
32 28 24
40 40 40
40 40 40 See Note 2 below.
40 40 40
30 25 20
40 40 40
32 28 24
40 40 40
40 40 40 See Note 2 below.
40 40 40
30 25 20
40 40 40
28 24 21
40 40 40
40 40 40 See Note 2 below.
40 40 40
25 20 15
40 40 40
24 21 18
40 40 40
40 40 40 See Note 2 below.
40 40 40
15 - -
Installer's Information Manual