Clearances And Height Requirements - Monessen Hearth NB18 Installation And Operating Instructions Manual

CLEARANCES
and
The dimensions shown in Figures 3 through 11 and defined in the
fireplace manufacturer's instructions are minimum clearances to
maintain when installing this heater. Left and right clearances are
determined when facing the front of the heater.
When heater is installed into a ventless firebox, minimum clearances,
as specified by the ventless firebox manufacturer, must be met.
Follow these instructions carefully to ensure safe installation. Failure
to follow instructions exactly can create a fire hazard.
Sidewall and ceiling clearances: The sides of the fire-
place opening must be at least 16" from any combustible
wall. The ceiling must be at least 42" from the top of the
fireplace opening.
16"
Figure 3 -
Sidewall and Ceiling Clearances
Table A - Heat Resistant Material Requirements with No Mantel or Combustible Projection
Heat Resistant
Material Measurement
12" or more
8" or less than 12"
Less than 8"
81D0107
HEIGHT REQUIREMENTS
42"
Requirements for Safe Installation
NB18
Hood not required
Hood not required
Extend heat resistant
material to 8" AND
install hood. Figure 4
Heat resistant material (minimum requirements) with
no wooden mantel or other combustible projection:
To install the gas logs into a fireplace with no wooden
mantel, shelf or other combustible projection above the
fireplace opening, measure the heat resistant material
height, according to Figure 4 and TABLE A.
Heat resistant materials such as slate and marble must be
at least 1/2" thick. Sheet metal should not be installed
onto combustible material.
IMPORTANT: If you cannot meet these minimum clear-
ances you must operate the heater with chimney flue
damper open. Refer to "Installing Vented Applications"
found on Page 17.
Figure 4 -
Measure Heat Resistant Material
Hood not required
Extend heat resistant material to 12" or install hood. Figure 4
Extend heat resistant material to 8" AND install hood.
Figure 5. OR, extend heat resistant material to a height of
at least 12"
NB18/NB24 Gas Log Set
Heat resistant
Material
Measure
This
Distance
FP2254
NB24
measure heat resist
Heater in
Fireplace/
Firebox
FP2254
7