Tempstar F97CMN Installation, Start-Up, Operating And Service And Maintenance Instructions page 40

F97CMN and G97CMN: Installation, Start-up, Operating and Service and Maintenance Instructions
1. Using winter design temperature (used in load calculations), find
appropriate temperature for your application and furnace model.
2. Determine the amount of total and exposed vent pipe.
3. Determine required insulation thickness for exposed pipe length(s).
4. When combustion air inlet piping is installed above a suspended
ceiling, the pipe MUST be insulated with moisture resistant
insulation such as Armaflex or other equivalent type of insulation.
NOTE: Maximum Equivalent Vent Length (MEVL) includes standard and concentric vent termination and does NOT include elbows. Use
Deductions from Maximum Equivalent Vent Length to determine allowable vent length for each application.
Unit Size
1 ½
Pipe Dia. (in)
0-2000 50
2001-3000 45
3001-4000 40
4001-4500
Altitude 35
4501-5000
(feet)
5001-6000 37
6001-7000 35
7001-8000 32
8001-9000 30
9001-10000 27
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Fig. 49 – Recommended Combustion Air Inlet Moisture Trap
Table 11 – Maximum Equivalent Vent Length - Ft.
60,000
2 2 ½ 3 1 ½
100 175 200
30
95 165 185
90 155 175 25
85 170 23
150
80 165
22
75 140 155
70 130 145 20
66 120 135 18
62 115 125 17
57 105 115 15
5. Insulate combustion air inlet piping when run in warm, humid
spaces.
6. Install the insulation per the insulation manufacturer's installation
instructions.
NOTE: Pipe length (ft. / M) specified for maximum pipe lengths located
in unconditioned spaces cannot exceed total allowable pipe length as
calculated from Table
Ft.
80,000
2 2 ½ 3 4
95 130 175 200 45
125 165 185 40
115 155 175 38
150 165
70 110 36
145 160
100 135 150 33
125 140 31
90
66 120 125 29
62 80 110 115 27
57 75 100 105 24
40
11.
100,000
2 2 ½ 3 4 2 ½
80 175 200
10
165 185
75
175 5
155
170
150 165
70
140 155
135 145 N/A
66 125 135
62 115 125
57 100 115
A170122A
Table 11 -
120,000
3 4
75 185
70 175
65 165
160
60
155
50 140
46 130
43 120
39 115