28
the top front edge of the Downdraft Diverter edge. The space
behind does not have to be filled (
Figure 61
).
The following Firebrick Patterns are available from MFI:
MFP(XX)SHBL- Herring Bone
Figure 62
MFP(XX)FRBL- Running Bond
Figure 63
Fireplace Finishes & Combustible Trim
Clearances
Hearth Material & Dimensions – Strict codes control
the types of materials that you can select for your Mason-Lite
Fireplace’s hearth as well as the hearth’s length and width. All
hearth extensions must be made of code-rated, noncombustible
materials such as tile, brick, concrete or stone.
As with any radiant heat fireplace, all MASON-LITE
Fireplaces must comply with building code safety clearances,
per units that have openings of 6 sq. ft. (six square feet) or
greater. For Mantel clearances see
Figure 17
. Walls that
Adjoin – Safety codes and all practical outlooks insist that your
fireplace cannot be installed closer than 2 ft. (two feet) to any
walls in the room the fireplace is housed in or to any walls of
adjoining rooms.
Caution in Regards to Combustibles – If any part of the fireplace
or objects in the room (curtains, rugs, paint, cushions, etc.) start
to show warping or discoloration due to heat from the fireplace,
it is time to take immediate action. Do not use the fireplace
until you have figured out how to address the problem. You are
facing a potential fire hazard. MFI cannot be responsible for the
make-up of material on the exterior of the fireplace you have
chosen, nor can MFI be held responsible for the materials in a
room that may be responding negatively to heat. However, in
almost all cases, there is a solution to the problem, either by
making adjustments to airflow or the modifications to the room
itself.
Installing Outside Air
The Mason-Lite Fireplace needs enough replacement
air to function properly and some local building codes may require
outside combustion air to be provided. If no replacement air is
provided, improper flue drafting may occur, creating negative
pressure whereby smoke may enter the home, especially in
homes that are very well insulated and tightly sealed. Check
local building codes for specific requirements.
Install Combustion Air Kit MFP4-AK into the MASON-
LITE Firebox through the side wall opening provided. A 4” dia.
hole will also be required through the firebrick side lining (see
Figure 64
). The tubing that goes out of the firebox wall must
feed into a flexible metal conduit as the source for outside
combustible air. It can go straight out through an outside wall
or into a ventilated crawl space. If crawl space is used, check
codes for proper termination.
Figure 64
Be sure that you carefully check the source of the outside air
before you choose the site for your air intake. You don’t want
a place where snow will collect, where bushes or trees will be
growing or a location that is too close to any other structure.
Install a screened termination cap to keep out small animals.