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56 Venting for Combustion Air
CAUTION
Do not start the vent run with a street elbow at
the vent collar. Using an elbow directly at the
collar will not allow for a tight seal between the
appliances and vent pipe. A length of straight
pipe must be used when starting the vent run.
●
To avoid moisture and frost build-up and to
maintain clearances to openings on adjacent
homes, 45° elbows, 90° elbows, or tees may be
attached to the end of the termination vent pipe
to direct the exhaust plumes away from buildings,
as long as the total allowable vent lengths,
maximum number of elbows, and distances to air
intake restrictions are observed.
●
Do not store hazardous or flammable substances
near the vent termination.
●
If this boiler will be installed in areas where
snow is known to accumulate, protect the vent
termination from blockage.
●
Ensure that the vent termination is at least 12 in
(300 mm) above the highest anticipated snow
line, or as required by local codes, whichever is
greater.
●
Support the vent pipe with hangers at regular
intervals or as required by local codes.
Exhaust and intake air pipes must be supported
at least every 4 ft (1.2 m).
●
The vent for this appliance shall not terminate
over public walkways; or near soffit vents or crawl
space vents or a nuisance or hazard or cause
property damage; or where condensate or vapor
could cause damage or could be detrimental to
the operation of regulators, relief valves, or other
equipment.
1. Measure 3.0” inches from the end of the vent
pipe, then draw a mark at that distance.
3.0”
Mark 3.0” from
the end of the pipe
2. Insert the pipe into the vent collar to start the
vent run. Make sure to completely slide the vent
into the collar until the end makes contact with
the bottom of the socket.
Note
Verify that 3.0” of the pipe has been
completely inserted into the collar and
that the mark is no longer visible.
3. Tighten the clamp with a socket wrench (8 mm)
to properly seal the joint.
Summary of Contents for NFB-175H
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