Specifications

Table 14 DEDUCTIONS FROM MAXIMUM EQUIVALENT VENT LENGTH - Feet (Meters)
Pipe Diameter (in): 1-1/2 2 2-1/2 3* 4*
Mitered 90 ° Elbow 8 (2.4) 8 (2.4) 8 (2.4)
Medium Radius 90 ° Elbow 5 (1.5) 5 (1.5) 5 (1.5)
Long Radius 90 ° Elbow 3 (0.9) 3 (0.9) 3 (0.9) 3 (0.9) 3 (0.9)
Mitered 45 -0Elbow 4 (1.2) 4 (1.2) 4 (1.2)
Medium Radius 45 ° Elbow 2.5 (0.8) 2.5 (0.8) 2.5 (0.8)
Long Radius 45 ° Elbow 1.5 (0.5) 1.5 (0.5) 1.5 (0.5) 1.5 (0.5) 1.5 (0.5)
Tee 16 (4.9) 16 (4.9) 16 (4.9) 16 (4.9) 16 (4.9)
* Note: 3- and 4-inch vent pipe systems require longradius elbows,
Venting System Length Calculations
The maximum length for each vent pipe (inlet or exhaust) equals the Maximum Equivalent Vent Length (MEVL) from Table 12 and
Table 13 minus the number of elbows multiplied by the deduction for each elbow in Table 14.
Standard vent terminations and concentric vent terminations count for zero deduction.
Example
A Direct-Vent 60,000 BTU/Hr furnace installed at 2100 ft altitude with 2-inch vent piping.
Venting system includes, FOR EACH PIPE, (3) 90 °-long radius elbows, (2) 450-long radius elbows and a concentric vent kit.
Table 15
(F/G)eMAC
Max. Heat
Input
Maximum Equivalent Vent Length
Deduct (3) 90 ° long radius elbows
Deduct (2) 45 ° long radius elbows
Winter
Design
Temp °F (°C)
20 (-10)
0 (-20)
-20 (-30)
-40 (-40)
Pipe Length
in Ft. &M
Ft.
M
Ft.
M
60000
Ft
M
Ft
M
= 127 ft Table 12
3x3ft = -9ft Table 14
2x 1.5ft = -3ft Table 14
Maximum vent length 115 ft (For EACH vent or inlet pipe)
Maximum Allowable Exposed Vent Lengths in Unconditioned Space
Maximum Length of Uninsulated and Insulated Vent Pipe-Ft (M)
No Insulation 3/8-in. (9.5 mm) 1/2-in. (12.7 mm)
Pipe Diameter-inches (mm) Pipe Diameter-inches (mm) Pipe Diameter-inches (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
(38) (51) (64) (76) (102) (38) (51) (64) (76) (102) (38) (51) (64)
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
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
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
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
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
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
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
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
3.0 4.0
(76) (102)
81.0 N/A
24.7 N/A
42.0 N/A
12.8 N/A
24.0 N/A
7.3 N/A
13.0 N/A
4.O N/A
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
20 (-10) 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
Ft. 22.0 16.0 14.0 7.0 O.0 35.0 69.0 60.0 49.0 35.0 35.0 83.0 72.0 60.0 45.0
0 (-20) M 6.7 4.9 4.3 2.1 O.0 10.7 21.0 18.3 14.9 10.7 10.7 25.3 21.9 18.3 13.7
80000
Ft. 11.0 5.0 2.0 O.0 O.0 35.0 46.0 39.0 29.0 16.0 35.0 57.0 48.0 37.0 23.0
-20 (-30) M 3.4 1.5 0.6 O.0 O.0 10.7 14.0 11.9 8.8 4.9 10.7 17.4 14.6 11.3 7.0
Ft. 4.0 O.0 O.0 O.0 O.0 35.0 33.0 26.0 17.0 4.0 35.0 41.0 34.0 24.0 11.0
-40 (-40) M 1.2 O.0 O.0 O.0 O.0 10.7 10.1 7.9 5.2 1.2 10.7 12.5 10.4 7.3 3.4
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
20 (-10) 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
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
0 (-20) 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
100000
Ft. N/A 8.0 6.0 O.0 O.0 N/A 50.0 49.0 38.0 23.0 N/A 50.0 60.0 48.0 32.0
-20 (-30) M N/A 2.4 1.8 O.0 O.0 N/A 15.2 14.9 11.6 7.0 N/A 15.2 18.8 14.6 9.8
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
-40 (-40) M N/A 0.3 O.0 O.0 O.0 N/A 12.8 10.4 7.8 3.0 N/A 15.2 13.1 9.8 5.5
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
20 (-10) 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
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
0 (-20) 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
120000
Ft. N/A N/A 10.0 2.0 O.0 N/A N/A 15.0 48.0 32.0 N/A N/A 15.0 59.0 42.0
-20 (-30) M N/A N/A 3.0 0.6 O.0 N/A N/A 4.6 14.6 9.8 N/A N/A 4.6 18.0 12.8
Ft. N/A N/A 1.0 O.0 O.0 N/A N/A 15.0 32.0 17.0 N/A N/A 15.0 41.0 25.0
-40 (-40) M N/A N/A 0.3 O.0 O.0 N/A N/A 4.6 9.8 5.2 N/A N/A 4.6 12.5 7.6
440 01 4201 01 Specificati ..... bject to change without notice. 47