Dunkirk Q90-200 Series II - Manual (Page 20)

20
Installation
1.
Recommend all pipes be cut, prepared, and pre-
assembled before permanently cementing any joint.
2.
Rigid supports cause excess noise in vent piping.
3.
Attach combustion air intake piping to supplied 2”
coupling on CVI gas valve. Attach vent piping to
furnished 2” CPVC vent tee on draft inducer outlet.
4.
All pipe joints are to be water tight.
5.
Working from boiler to outside, cut pipe to required
length(s).
6.
Deburr inside and outside of pipe. Remove all chips and
shavings.
7.
Chamfer outside edge of pipe for better distribution of
primer and cement.
8.
Clean and dry all surfaces to be joined.
9.
Check dry fit of pipe and mark insertion depth on pipe.
10.
After pipes have been cut and pre-assembled, apply
cement primer to pipe fitting socket and end of pipe to
insertion mark. Quickly apply approved cement to end
of pipe and fitting socket (over primer). Apply cement
in light, uniform coat on inside of socket to prevent
buildup of excess cement. Apply second coat.
11.
While cement is still wet, insert pipe into socket with
¼ turn twist. Be sure pipe is fully inserted into fitting
socket.
12.
Wipe excess cement from joint. Continuous bead of
cement will be visible around perimeter of properly
made joint.
13.
Handle pipe joint carefully until cement sets.
14.
Support combustion air and vent piping minimum of
every 5 feet using pre-formed metal hanging straps. Do
not rigidly support pipes. Allow for movement due to
expansion and contraction.
15.
Slope combustion air and vent pipes toward boiler
minimum of ¼” per linear foot with no sags between
hangers.
16.
Use appropriate methods to seal openings where vent
and combustion air pipes pass through roof or side
wall.
7 - COMBUSTION AIR AND VENT PIPE