59MN7C: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
37
3. For each pipe, multiply the number of elbows by the equivalent
length for the type of elbow used. Record the equivalent length of
all the elbows for each pipe.
4. If a Tee is used on the termination (Alberta and Saskatchewan,
when required) record the equivalent length of the Tee used.
5. Calculate Total Equivalent Vent Length by adding the equivalent
lengths of the fittings to the lengths of the individual vent and
combustion air pipes.
6. When using polypropylene venting systems with flexible vent
pipes, perform adjustments for the equivalent length of the flexible
vent pipe to the calculated total equivalent venting system length.
See the polypropylene vent system manufacturer’s instructions for
details.
7. Select a diameter of vent pipe from Table 12 and note the
Maximum Equivalent Vent Length (MEVL) shown for that
application for that specific furnace input size. Compare the Total
Equivalent Vent Length (TEVL) to the MEVL:
8. If the Total Equivalent Vent Length is shorter than the Maximum
Equivalent Vent Length for the diameter of pipe chosen, then that
diameter of pipe selected may be used.
9. If the Total Vent Length is longer than the Maximum Equivalent
Vent Length for the diameter of pipe chosen, that diameter pipe
MAY NOT be used for venting the furnace. Try the next larger
diameter pipe
.
NOTE: If the calculated Total Equivalent Vent Lengths results in
different diameter pipes for the vent and combustion air, select the larger
diameter for both pipes.
NOTE: If the Maximum Vent Length for diameter of the pipe selected is
longer than the measured length and the equivalent length of all the
fittings and terminations (TEVL), recalculate Total Equivalent Vent
Length using the next smaller diameter. If the Maximum Equivalent
Vent Length is still longer than the longer TEVL of the vent pipe or
combustion air pipe, then that diameter of pipe selected may be used.
When installing vent systems pipe lengths of 10 ft. (3 M) or less, use the
smallest allowable pipe diameter. Using a pipe size greater than required
for short venting systems may result in loss of efficiency, incomplete
combustion, flame disturbance, or flame sense lockout.
For vent systems longer than 10 ft. (3 M), any larger diameter vent pipe
shown in Table 12 FOR THAT SIZE FURNACE may be used.
A170122A
Fig. 50 – Recommended Combustion Air Inlet Moisture Trap
NOTE: Maximum Equivalent Vent Length (MEVL) includes standard and concentric vent termination and does NOT include elbows. Use Table 12 -
Deductions from Maximum Equivalent Vent Length to determine allowable vent length for each application.
Table 12 – Maximum Equivalent Vent Length - Ft.
Representative drawing only, some models may vary in appearance.
TO CODE--APPROVED DRAIN OR CONDENSATE PUMP
Tee
Dry Well
Cap
(water tight
and removable)
Tee
Dry Well
Cap
(water tight
and removable)
Tee
Dry Well
Cap
(water tight
and removable)
Recommend “T” fitting with 4--inch minimum height standpipe (A) of same diameter or larger extending upward.
A
A
A
Ft.
Unit Size 60,000 80,000 100,000 120,000
Altitude
(feet)
Pipe Dia. (in)
1 ½ 2 2 ½ 3 1 ½ 2 2 ½ 3 4 2 2 ½ 3 4 2 ½ 3 4
0-2000 50 100 175 200
30
95 130 175 200 45 80 175 200
10
75 185
2001-3000 45 95 165 185
70
125 165 185 40
75
165 185 70 175
3001-4000 40 90 155 175 25 115 155 175 38
155
175 5 65 165
4001-4500
35
85
150
170 23
110
150 165
36
70
170
N/A
60
160
4501-5000 80 165
22
145 160 150 165
5001-6000 37 75 140 155 100 135 150 33 140 155 155
6001-7000 35 70 130 145 20
90
125 140 31 135 145 50 140
7001-8000 32 66 120 135 18 66 120 125 29 66 125 135 46 130
8001-9000 30 62 115 125 17 62 80 110 115 27 62 115 125 43 120
9001-10000 27 57 105 115 15 57 75 100 105 24 57 100 115 39 115
Maximum Equivalent Vent Length - Meters
Meters
Unit Size 60,000 80,000 100,000 120,000
Altitude
(meters)
Pipe Dia.
(mm)
38 51 64 76 38 51 64 76 102 51 64 76 102 64 76 102
0-610 15.2 30.4 53.3 60.9
9.1
28.9 39.6 53.3 60.9 13.7 24.3 53.3 60.9
3.0
22.8 56.3
611-914 13.7 28.9 50.2 56.3
21.3
38.1 50.2 56.3 12.1
22.8
50.2 56.3 21.3 53.3
915-1219 12.1 27.4 47.2 53.3 7.6 35.0 47.2 53.3 11.5
47.2
53.3 1.5 19.8 50.2
1220-1370
10.6
25.9
45.7
51.8 7.0
33.5
45.7 50.2
10.9
21.3
51.8
NA
18.2
48.7
1371-1524 24.3 50.2
6.7
44.1 48.7 45.7 50.2
1525-1829 11.2 22.8 42.6 47.2 30.4 41.1 45.7 10.0 42.6 47.2 47.2
1830-2134 10.6 21.3 39.6 44.1 6.0
27.4
38.1 42.6 9.4 41.1 44.1 15.2 42.6
2135-2438 9.7 20.1 36.5 41.1 5.4 20.1 36.5 38.1 8.8 20.1 38.1 41.1 14.0 39.6
2439-2743 9.1 18.8 35.0 38.1 5.1 18.8 24.3 33.5 35.0 8.2 18.8 35.0 38.1 13.1 36.5
2744-3048 8.2 17.3 32.0 35.0 4.5 17.3 22.8 30.4 32.0 7.3 17.3 30.4 35.0 11.8 35.0
To Next Page
