Mendota FV48, Инструкция по установке и эксплуатации

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85-03-01194 FV48 Page 25
Clearances to Combustible Side Walls
The minimum distance required from the side edge of the visible glass to a combustible side wall is 16 ” . Combustible side walls,
mantel corbels, mantel legs and other combustible walls and decorative objects must fall behind a 45-degree line extending
outward from the side edges of the visible glass unless such objects are more than 16
” away from the visible side edges of the
glass. See
Figure 3-19 Side Wall Clearances.
If the required clearance cannot be m et to a pre-existing combustible side wall, an NFPA approved clearance
reduction shield, metal or ceramic board, must be added to the side wall.
Horizontal Clearance Reduction by 66%
NPFA 211 Approved : Install 20-gauge or
heavier steel shield that provides at least a
1” active airspace, on the combustible wall
surface. To provide for active airflow, install
at least 1” metal or ceramic standoffs or
spacers between the metal shield and the
combustible surface being protected. The
bottom and top edges of the cavity between
the metal shield and the combustible
surface must be left open. The steel shield
must be a minimum of 12” larger in each
direction than the surface area of the source
of heat; or if the surface being protected is
smaller than surface area of the source of
heat, this shield must be larger than the
combustible surface in each direction.
By using this method of protection, if the
required horizontal clearance was 16
” , the
resulting clearance will be reduced by 66%
to 5-3/8
” between the heat source and the
metal shield.
Horizontal Clearance Reduction by 50%
NPFA 211 Approved : Install an R-1 rated ceramic board or R-1 rated mineral board on the wall you are attempting to protect.
by using this method of protection, if the required horizontal clearance was 16 ” , the resulting clearance will be reduced by 50%
to 8 ” between the heat source and the R-1 Rated wall board.
Figure 3-19 Side Wall Clearances