Instruction manual

43
Table 12 – Maximum Allowable Exposed Vent Lengths Insulation Table -- Ft. / M
Maximum Length of Uninsulated and Insulated Vent Pipe-Ft (M)
Modulating
Furnace
High Heat
Input
Winter
Design Temp
°F(° C)
Pipe Length
in Ft. & M
No Insulation 3/8-in. (9.5 mm) 1/2-in. (12.7 mm)
Pipe Diameter-in. (mm) Pipe Diameter-in. (mm) Pipe Diameter-in. (mm)
1.5 2.0 2.5 3.0 4.0 1.5 2.0 2.5 3.0 4.0 1.5 2.0 2.5 3.0 4.0
(38) (51) (64) (76) (102) (38) (51) (64) (76) (102) (38) (51) (64) (76) (102)
60000
20 (-10)
Ft. 34.0 29.0 28.0 23.0 N/A 55.0 88.0 79.0 69.0 N/A 55.0 104.0 93.0 81.0 N/A
M 10.4 8.8 8.5 7.0 N/A 16.8 26.8 24.1 21.0 N/A 16.8 31.7 28.3 24.7 N/A
0 (-20)
Ft. 14.0 9.0 7.0 0.0 N/A 55.0 49.0 43.0 34.0 N/A 55.0 60.0 52.0 42.0 N/A
M 4.3 2.7 2.1 0.0 N/A 16.8 14.9 13.1 10.4 N/A 16.8 18.3 15.8 12.8 N/A
-20 (-30)
Ft. 5.0 0.0 0.0 0.0 N/A 41.0 32.0 26.0 18.0 N/A 50.0 40.0 33.0 24.0 N/A
M 1.5 0.0 0.0 0.0 N/A 12.5 9.8 7.9 5.5 N/A 15.2 12.2 10.1 7.3 N/A
-40 (-40)
Ft. 0.0 0.0 0.0 0.0 N/A 30.0 21.0 16.0 8.0 N/A 37.0 28.0 22.0 13.0 N/A
M 0.0 0.0 0.0 0.0 N/A 9.1 6.4 4.9 2.4 N/A 11.3 8.5 6.7 4.0 N/A
80000
20 (-10)
Ft. 35.0 39.0 39.0 33.0 25.0 35.0 118.0 107.0 92.0 76.0 35.0 130.0 125.0 109.0 90.0
M 10.7 11.9 11.9 10.1 7.6 10.7 36.0 32.6 28.0 23.2 10.7 39.6 38.1 33.2 27.4
0 (-20)
Ft. 22.0 16.0 14.0 7.0 0.0 35.0 69.0 60.0 49.0 35.0 35.0 83.0 72.0 60.0 45.0
M 6.7 4.9 4.3 2.1 0.0 10.7 21.0 18.3 14.9 10.7 10.7 25.3 21.9 18.3 13.7
-20 (-30)
Ft. 11.0 5.0 2.0 0.0 0.0 35.0 46.0 39.0 29.0 16.0 35.0 57.0 48.0 37.0 23.0
M 3.4 1.5 0.6 0.0 0.0 10.7 14.0 11.9 8.8 4.9 10.7 17.4 14.6 11.3 7.0
-40 (-40)
Ft. 4.0 0.0 0.0 0.0 0.0 35.0 33.0 26.0 17.0 4.0 35.0 41.0 34.0 24.0 11.0
M 1.2 0.0 0.0 0.0 0.0 10.7 10.1 7.9 5.2 1.2 10.7 12.5 10.4 7.3 3.4
100000
20 (-10)
Ft. N/ A 47.0 47.0 41.0 32.0 N/A 50.0 110.0 112.0 93.0 N/A 50.0 110.0 132.0 110.0
M N/A 14.3 14.3 12.5 9.8 N/A 15.2 33.5 34.1 28.3 N/A 15.2 33.5 40.2 33.5
0 (-20)
Ft. N/ A 21.0 19.0 12.0 1.0 N/A 50.0 74.0 61.0 45.0 N/A 50.0 89.0 74.0 57.0
M N/A 6.4 5.8 3.7 0.3 N/A 15.2 22.6 18.6 13.7 N/A 15.2 27.1 22.6 17.4
-20 (-30)
Ft. N/ A 8.0 6.0 0.0 0.0 N/A 50.0 49.0 38.0 23.0 N/A 50.0 60.0 48.0 32.0
M N/A 2.4 1.8 0.0 0.0 N/A 15.2 14.9 11.6 7.0 N/A 15.2 18.3 14.6 9.8
-40 (-40)
Ft. N/ A 1.0 0.0 0.0 0.0 N/A 42.0 34.0 24.0 10.0 N/A 50.0 43.0 32.0 18.0
M N/A 0.3 0.0 0.0 0.0 N/A 12.8 10.4 7.3 3.0 N/A 15.2 13.1 9.8 5.5
120000
20 (-10)
Ft. N/ A N/A 15.0 49.0 40.0 N/A N/A 15.0 100.0 111.0 N/A N/A 15.0 100.0 131.0
M N/A N/A 4.6 14.9 12.2 N/A N/A 4.6 30.5 33.8 N/A N/A 4.6 30.5 39.9
0 (-20)
Ft. N/ A N/A 15.0 17.0 6.0 N/A N/A 15.0 75.0 57.0 N/ A N/A 15.0 90.0 70.0
M N/A N/A 4.6 5.2 1.8 N/A N/A 4.6 22.9 17.4 N/A N/A 4.6 27.4 21.3
-20 (-30)
Ft. N/ A N/A 10.0 2.0 0.0 N/A N/A 15.0 48.0 32.0 N/A N/A 15.0 59.0 42.0
M N/A N/A 3.0 0.6 0.0 N/A N/A 4.6 14.6 9.8 N/A N/A 4.6 18.0 12.8
-40 (-40)
Ft. N/ A N/A 1.0 0.0 0.0 N/A N/A 15.0 32.0 17.0 N/A N/A 15.0 41.0 25.0
M N/A N/A 0.3 0.0 0.0 N/A N/A 4.6 9.8 5.2 N/A N/A 4.6 12.5 7.6
* Pipe length (ft) specified for maximum pipe l engths located in unconditioned spaces. Pipes located in unconditioned space cannot exceed total allowable pipe
length calculated from Table 13 or 15.
† Insulation thickness based on R value of 3.5 per in.
987MA