Page 25
TABLE 7
Maximum Allowable Exhaust Vent Pipe Length (in ft.)
3
Without Insulation In Unconditioned Space For
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Winter Design
Temp
1
°F (°C)
Vent
Pipe
Diam
Unit Input Size
030
045 070 090 110
32 to 21
(0 to -6)
PVC
2
PP PVC
2
PP PVC
2
PP PVC
2
PP PVC
2
PP
1-1/2 in
N/A N/A
25 N/A 20 N/A N/A N/A N/A N/A
2 in 18 16 31 28 50 48 30 30
2-1/2 in 13 N/A 24 N/A 42 N/A 56 N/A
3 in 9 9 18 18 35 35 47 47
20 to 1
(-7 to -17)
1-1/2 IN 15 N/A 20 N/A N/A N/A N/A N/A
2 in 9 8 18 16 32 29 30 30
2-1/2 in 5 N/A 13 N/A 24 N/A 34 N/A
3 in 1
1
8 8 19 19 26 26
0 to -20
(-18 to -29)
1-1/2 in 10 N/A 15 N/A N/A N/A N/A N/A
2 in 5
3
12 10 22 19 30 27
2-1/2 in 1
N/A
7 N/A 15 N/A 22 N/A
3 in N/A
N/A
2 2 10 10 16 16
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127(&RQFHQWULFWHUPLQDWLRQVDUHWKHHTXLYDOHQWRI¶DQGVKRXOGEHFRQVLGHUHGZKHQPHDVXULQJSLSHOHQJWK
127(0D[LPXPXQLQVXODWHGYHQWOHQJWKVOLVWHGPD\LQFOXGHWKHWHUPLQDWLRQYHQWSLSHH[WHULRUWRWKHVWUXFWXUHDQGFDQQRWH[FHHGOLQHDUIHHWRU
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127(,ILQVXODWLRQLVUHTXLUHGLQDQXQFRQGLWLRQHGVSDFHLWPXVWEHORFDWHGRQWKHSLSHFORVHVWWRWKHIXUQDFH6HH)LJXUH
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Conditioned
Space
Unconditioned
Space
Exhaust
Pipe
Intake
Pipe
Conditioned
Space
Pipe Insulation
Figure 31