For either a confined or unconfined space in a building of
tight construction with inadequate infiltration, air must be
drawn from the outdoors or from spaces that freely
communicate with the outdoors. Two permanent openings
located as indicated above are to be provided as follows:
1.
When communicating with outdoors directly or by
means of vertical ducts, each opening shall have a
free area of not less than one square inch per 4,000
BTU/Hr of total input of all appliances in the space.
2.
When communicating with outdoors by means of
horizontal ducts, each opening shall have a free area
of not less than one square inch per 2,000 BTU/Hr of
total input of all appliances in the space.
For detailed requirements see:
•
In Canada, CAN/CGA- B149 Installation Codes
•
In U.S.A., ANSI Z223. 1 /NFPA 54, National Fuel Gas
Code.
WARNING!
1.
Flammable materials gasoline, pressurized
containers, or any other items or articles that are
potentially fire hazards must never be placed on or
adjacent to the heater. The appliance area must be
kept free of all combustible materials, gasoline and
other flammable vapors and liquids.
2.
Do not obstruct the flow of combustion and
ventilation air to the appliance.
CLEARANCE
In Canada
The WR 325 and the WR 400 are design certified for
installation on a combustible wall (for the WR 325 the wall
bracket supplied with the unit must be used for mounting to
combustible construction), and for installation in an alcove
or closet with minimum clearances to 0 mm from back, 102
mm (4 inches) from sides, 305 mm (12 inches) from top and
bottom, and 102 mm (4 inches) from front. A minimum of
305 mm (12 inches) shall be allowed for maintenance of
serviceable parts.
Clearence from vent is dependant upon the clearence rating
of the venting material used; that is, type B-1 vent is approved
for 1 inch clearence, B-2 vent for 2 inch, etc.
In United States
The WR 325 and the WR 400 are design certified for
installation on a combustible wall (for the WR 325 the wall
bracket supplied with the unit must be used for mounting to
combustible construction), and for installation in an alcove
with minimum clearences to combustible construction of 0
mm from back, 102 mm (4 inches) from sides, 305 mm (12
inches) from top and bottom. In addition, the WR 325 has
also been design certified for closet installation with minimum
clearences to combustible construction of 0 mm from back,
102 mm (4 inches ) from sides, 305 mm (12 inches) from
top and bottom, and 102 (4 inches) from front. A minimum