Raypak Xfiire 300B, Инструкция по установке и эксплуатации

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13
Motorized Combustion Air Dampers D-37
or Louvers
When motorized dampers or louvers are used for
combustion air, they must be interlocked with each
appliance in the equipment room, to ensure proper
operation.
See Field Wiring Connection section of this manual for
proper wiring instructions, using Fan/Damper dry contacts
and external interlock.
A A WARNING: When unit is installed in the freezing
climates using ducted combustion air, a motorized
damper must be used and must be interlocked with the
heater per NFGC requirements.
CAUTI ON: All ducting must be self-supported.
Air Supply
U.S. Installations
All Air from Inside the Building
The confined space shall be provided with TWO
permanent openings communicating directly with an
additional room(s) of sufficient volume so that the
combined volume of all spaces meets the criteria for a
room large in comparison (NFGC). The total input of all
gas utilization equipment installed in the combined space
shall be considered in making this determination. Each
opening shall have a minimum free area of 1 square inch
per 1,000 BTUH (2,225 mm² per kW) of the total input
rating of all gas utilization equipment in the confined
space, but not less than 100 square inches (645 cm²). One
opening shall commence within 12" (305 mm) of the top,
and one opening shall commence within 12" (305 mm)
of the bottom of the enclosure. The minimum dimension
of air openings shall be not less than 3" (76 mm) in any
direction.
All Air from Outdoors
The confined space shall communicate with the outdoors
in accordance with one of the methods below. The
minimum dimension of air openings shall not be less than
3" (76 mm) in any direction. Where ducts are used, they
shall be of the same cross-sectional area as the net free
area of the openings to which they connect.
4. Two permanent openings, one commencing within
12" (305 mm) of the top, and one commencing within
12" (305 mm) of the bottom of the enclosure, shall be
provided. The openings shall communicate directly,
or by ducts, with the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors.
a. Where directly communicating with the outdoors
or where communicating to the outdoors through
vertical ducts, each opening shall have a
minimum free area of 1 square inch per 4,000
BTUH (550 mm² per kW) of total input rating of
all equipment in the enclosure.
b. Where communicating with the outdoors through
horizontal ducts, each opening shall have a
minimum free area of 1 square inch per 2,000
BTUH (1,100 mm² per kW) of total input rating of
all equipment in the enclosure.
5. One permanent opening, commencing within
12" (305 mm) of the top of the enclosure, shall be
permitted where the equipment has clearances of
at least 1" (25 .4 mm) from the sides and back and
6" (152 mm) from the front of the appliance. The
opening shall directly communicate with the out-
doors or shall communicate through a vertical or
horizontal duct to the outdoors or spaces that freely
communicate with the outdoors, and shall have a
minimum free area of:
a.
1 square inch per 3,000 BTUH (740 mm² per kW)
of the total input rating of all equipment located
in the enclosure, and
b. Not less than the sum of the areas of all vent
connectors in the confined space.
A A WARNING: Do not use the “one permanent opening”
method if the equipment room is under negative-
pressure conditions.
Canadian Installations
A A CAUTION: All combustion air must be drawn from
the air outside of the building; the mechanical equipment
room must communicate directly with the outdoors.
Ventilation of the space occupied by the heater shall be
provided by an opening(s) for ventilation air at the highest
practical point communicating with the outdoors. The total
cross-sectional area of such an opening(s) shall be at
least 10% of the area required below, but in no case shall
the cross-sectional area be less than 10 square inches
(65 cm²).
A A WARNING: Make sure that the equipment room is
not under negative-pressure conditions.
When air supply is provided by natural air flow from
outdoors for a power burner and there is no draft regulator,
drafthood or similar flue gas dilution device installed in the
same space, in addition to the opening for ventilation air
required above, there shall be a permanent air supply
opening(s) having a total cross-sectional area of not less
than 1 square inch for each 30,000 BTUH (74 mm² per kW)
of total rated input of the burner(s), and the location of the
opening(s) shall not interfere with the intended purpose of
the opening(s) for ventilation air referred above.