Fireplace Installation - USSC APS1100B Owner's Manual

"FIREPLACE" INSTALLATION (CONT'D)

FIREPLACE INSTALLATION

Connection of the stovepipe directly into the ex-
isting masonry chimney over the fireplace open-
ing is a more desirable method. This installation
performs better, yielding more heat and better
draft; it is also easy to clean and inspect for
creosote. Before beginning this type of installa-
tion plan carefully; a high degree of skill is re-
quired to insure safety.
An entry port for the stovepipe must be cut through
the chimney with minimum damage to the fireclay
liner. Some involved measurements may be
required to locate the flue liner exactly. Before
cutting, take time to mark the size and position of
the entry port. Position the entry port so that at
least 8 inches of the flue liner remains below the
port.
Keep in mind that wood mantels and combustible
trim around the fireplace must have adequate
clearances from the heater and stovepipe or must
be protected in an approved manner. Also, be
sure to leave at least an 18 inch clearance be-
tween the top of the stovepipe and the combus-
tible ceiling or other combustibles. Placing the
center of the entry port 2 feet below the ceiling will
insure proper clearance for 6-inch, 8-inch, and
10-inch stovepipes. Next, install a fireclay (at
least 5/8 inch thick) or metal thimble, being sure
that the thimble is flush with the inner flue lining,
secure the thimble in place with refractory mortar.
The thimble should be surrounded on all sides
with 8 inches of brickwork (solid masonry units) or
24 inches of stone.
Install the stovepipe as far as possible into the
thimble, but not past the inside of the flue lining.
There should be a small airspace (approximately
1/2 inch) between the stovepipe and thimble,
allowing for expansion of the stovepipe. Seal this
airspace with high-temperature caulking or ce-
ramic wool. Finally, be sure to wire the damper in
the fireplace closed and apply the same sealant
you used at the stovepipe and thimble junction.
Do not use the Type B installation (not illustrated
in this manual), that is, venting up through the
fireplace opening, regardless of whether the fire-
place opening is closed.
Masonry chimneys have several positive at-
tributes: If properly built, they are quite durable,
and most homeowners consider them more at-
tractive perhaps than an unenclosed factory built
chimney. And, if the chimney is located within the
confines of the house (that is, not attached to an
exterior wall), its mass alone will store heat longer
and continue to release the heat long after the fire
has died. Masonry chimneys have many disad-
vantages though. Masonry chimneys constructed
on an exterior wall are exposed to cold outdoor
temperatures, promoting greater heat loss, higher
accumulations of creosote, and reduced draft
which leads to poorer heater or furnace perfor-
mance.
10
Fig. 10