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2) COMBUSTION AIR
(a) WARNING: If the area in which the appliance is to be operated is smaller than
750
cubic feet, or it the building is of an unusually tight construction, adequate
combustion and ventilation air must be provided by one of the methods
described in the
National Fuel Gas Code
ANSI Z223.l/NFPA 54, Air for
Combustion and Ventilation, or applicable local codes.
Unusually tight construction is defined as construction where:
(1) Walls and ceilings exposed to the outside atmosphere have a continuous
water vapor retarder with a rating of 1 penn (6 x 10 “kg per pa-sec-m2) or less
with openings gasketed or sealed;
(2) Weather stripping has been added on openable windows and doors; and
(3) Caulking or sealants are applied to areas such as joints around window and
door frames, between sole plates and floors, between wall-ceiling joints,
between wall panels, at penetrations for plumbing, electrical, gas lines, and at
other openings.
(b) The Old Salem coal set has been equipped with an oxygen depletion system
to prevent reduction of the oxygen level in the installation room from reaching a
level below 18 percent. The above requirements are provided to prevent the
unlikely occurrence of this level
.
3) MINIMUM CLEARANCE TO COMBUSTIBLES:
When the Old Salem ventfree coal burner is installed in a non-combustible
fireplace, the mantel, if used, may extend up to 12 inches maximum from the wall
and must be located a minimum of 18 inches above the top of the fireplace
opening. The underside of the mantel should be protected by a high temperature
paint or application of a non combustible lamination.
When installed in a corner location, there must be a minimum clearance of 10
inches from the outer edge of the fireplace opening and the corner wall with the
intervening space made of non combustible materials, cast iron surround,
masonry, tile etc. there must be a non combustible hearth extending a minimum of
14 inches in front of the firebox.
Overall minimum clearances to combustibles on the outside of firebox are:
Sides: 6”
Top: 18”
Hearth: 14”