SCF-050 Manual
14
Venting into an Existing Chimney
Figure 6
The Furnace may be connected to an existing Class A chimney or a masonry chimney which meets the
minimum requirements of NFPA 211.
1.
If the Furnace’s exhaust is connected to a masonry chimney, the masonry chimney must be free of
cracks that could leak exhaust gases or fly ash.
A relining of the chimney with either PL vent or
single wall stainless steel pipe may be necessary to bring the chimney into compliance.
2.
When chimneys are relined, a chimney chase cap that reduces the outlet of the chimney to the size
of the liner is required. Extend the exhaust vent above the chimney chase cap and finish it off with
a rain cap
. A single wall liner may need to be wrapped with insulation to maintain adequate
exhaust temperatures when outside temperatures drop below freezing, causing the flue
temperatures to become too low.
3.
Venting into the side of an existing masonry chimney must be done through a masonry thimble.
When wall penetration is necessary to access a masonry chimney, use a listed PL vent wall
thimble. (Figure 6).
4. When venting into a Class A steel chimney use an appropriate PL Vent adapter.
