Installation manual

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108918-01K 5
HEARTH EXTENSION
Ahearthextensionprojectingaminimumof
16"infrontofandaminimumof8"beyond
eachsideofreplaceopeningisrequiredto
protectcombustibleoorconstructioninfront
of replace. Fabricate a hearth extension
using a material which meets the following
specications: a layer of noncombustible,
inorganicmaterialhavingathermalconductiv-
ityofK=0.84BTUIN/FT,HR.F(orless)at1"
thick.For example,if materialselected has
a K factor of 0.25, such as glass ber, the
followingformulawouldapply:
 0.25x1.0"=0.30"thicknessrequired
 0.84
Thermalconductivity"K"ofmaterialscanbe
obtained from manufacturer or supplier of
noncombustiblematerial.Ifhearthextension
istobecovered,usenoncombustiblemate-
rialsuchastile,slate,brick,concrete,metal,
glass,marble,stone, etc. Providea means
topreventhearthextensionfromshiftingand
sealgapbetweenreplaceframeandhearth
extension with a noncombustible material
(seeFigure3).
WARNING: Hearth extension
is to be installed only as shown
in Figure 3.
FIREPLACE INSTALLATION
Continued
Figure 3 - Hearth Extension
SealGap
FireplaceFront
EmberProtector
FireplaceFront
RaisedHearth
FireplaceFront
Elevated
EmberProtector
EmberProtector
SealGap
Hearth
Extension
SealGap
FireplaceFront
EmberProtector
FireplaceFront
Elevated
DoNotBlockLouver
EmberProtector
SealGap
Hearth
Extension
Hearth Extension, Circulating Modes
Hearth Extension, Noncirculating Models
NO