Instinct Venting Manual

2 Inch Vent Pipe
PVC or CPVC
Material
2 Inch Vent Pipe
Min. 7 Feet Length
CPVC Material
3 x 2 Bell Reducer
CPVC Material
3 Inch Stub Vent Pipe
CPVC Material
2 Inch Vent Pipe
PVC or CPVC
Material
2 Inch Vent Pipe
CPVC Material
2 Inch 90º
Long Sweep Elbow
CPVC Material
3 x 2 Bell Reducer
CPVC Material
3 Inch Stub Vent Pipe
CPVC Material
25
CHAPTER 4
Fig. 21 - 2” CPVC/PVC Venting System Vertical
4.1. Vent/Combustion Air Transitions
4.1.1 3” to 2” Transitions
This chapter outlines the installation of 2” Vent-
ing and Combustion Air Piping for the INSTINCT
units when the vent system must transition
from the 3” outlet of the boiler to the 2” vent
system.
1. The transition from 3” vent system to 2” vent system
must occur at the boiler vent outlet.
2. The transition from 3” vent to 2” vent must occur in
a vertical run only.
Transition of 3” vent to 2” vent in a horizontal
run will result in pooling of the condensate
and potential vent blockage. Failure to tran-
sition from 3” vent to 2” vent in a vertical run
can result in substantial property damage, seri-
ous injury, or death.
3. Use a 3” x 2” bell reducer to make the transition to
2” CPVC/PVC vent, see Figs. 21 and 22.
4. The 2” vent must not transition back to 3” vent at
any point in the vent system.
5. The PVC combustion air piping shall transition from
3” to 2” using a 3” x 2” bell reducer and shall transition
in a similar manner as the vent system.
6. The total equivalent length of the 3” and 2” vent pip-
ing combined shall not exceed the length listed for
a 2” vent system in Table 2 on page 4.
7. The total equivalent length of 3” and 2” combustion
air piping combined shall not exceed the length
listed for a 2” combustion air system in Table 2 on
page 4.
NOTICE
WARNING
Fig. 22 - 2” CPVC/PVC Venting System Horizontal
CHAPTER 4 - INSTALLATION REQUIREMENTS