Installation / Operation Instruction Manual

Installation instructions
RTG 199 ME – 6 720 811 615 (2014/05)
14
Combustion air
Calculation example for 4" venting:
Exhaust
Combustion air
System used Concentric
Number of 90° elbows needed: 1
Number of 45° elbows needed: 2
Table 11
Calculation of example
Max. length 28.5’
90° elbow reduction - 2.5’
sub-total = 26’
45° elbow reduction - 2.5’
Total = 23.5’
Table 12
For this example, the maximum allowable exhaust pipe
length is 23.5 feet.
System used Concentric
Number of 90° elbows needed: 2
Number of 45° elbows needed: 1
Table 13
Calculation of example
Max. length 28.5’
90° elbow reduction - 5’
sub-total = 23.5’
45° elbow reduction - 1.25’
Total = 22.25’
Table 14
For this example, the maximum allowable combustion
air pipe length is 22.25 feet.
System used Twin pipe
Number of 90° elbows needed: 2
Number of 45° elbows needed: 2
Table 15
Calculation of example
Max. length 61.25’
90° elbow reduction - 2.5’
sub-total = 58.75’
45° elbow reduction - 1.5’
Total = 57.25’
Table 16
For this example, the maximum allowable exhaust pipe
length is 57.25 feet.
System used Twin pipe
Number of 90° elbows needed: 1
Number of 45° elbows needed: 2
Table 17
Calculation of example
Max. length 61.25’
90° elbow reduction - 1.25’
sub-total = 60’
45° elbow reduction - 1.5’
Total = 58.5’
Table 18
For this example, the maximum allowable combustion
air pipe length is 58.5 feet.