Harsco Industrial SC-2000 Installation & Owner's Manual page 21

3.5.2.1 Air Inlet Requirements — United States (
Under no circumstances shall
the boiler room ever be under a
negative pressure. Particular
care should be taken when
exhaust fans, compressors, air-
handling units or other equipment
may rob air from the boiler. Note
that this equipment might be in
rooms other than the boiler room.
This applies to both sealed
combustion and atmospheric room
combustion air applications.
N :
OTE
1. The required size of openings for
combustion and ventilation air shall
be based on the net free area of the
opening.
2. Screens shall be not smaller than ¼".
3. Motorized louvers shall be
interlocked with the appliance so that
they are proven open prior to main
burner ignition and operation.
When using two permanent openings, one opening shall commence within 12 inches above the floor and the other
within 12 inches below the ceiling, preferably on opposite walls. The openings shall communicate directly, or by way
of ducts, with free outdoor air. The minimum net free area of the openings shall be calculated in accordance with the
following:
When air is taken directly from outside the building, each opening (minimum of two, as outlined above), 1 square
•
inch for each 4,000 Btu per hour (550 mm
When air is taken from the outdoors through a vertical duct into the mechanical room, 1 square inch per 4,000 Btu
•
per hour (550 mm /kW) of total boiler input is required.
2
When air is taken from the outdoors through a horizontal duct into the mechanical room, 1 square inch per 2,000 Btu
•
per hour (1100 mm
Table 3.5.2.1 US Minimum area of ventilation openings per boiler (sq inches)
P-K SONIC™
Boiler Model
SAME FLOOR
SC-2000
SC-3000
SC-4000
Harsco Industrial, Patterson-Kelley Technical Service 1.877.728.5351
When air is supplied from inside the building, the total required volume
shall be the sum of the required volume for all the appliances located
in the mechanical room. Adjacent rooms furnished with fixed openings
communicating directly with the mechanical room are considered part
of the required volume. The minimum volume is 50 ft
(4.8 m
Openings used to connect indoor spaces to obtain the required
minimum volume shall be sized as follows:
When combustion air is supplied from outside the building, the boiler
room shall be provided with one or two openings to ensure adequate
combustion air and proper ventilation.
When using one permanent opening, the opening shall commence
within 12 inches of the ceiling and shall communicate directly with the
outdoors or through a vertical or horizontal duct that communicates to
the outdoors.
Minimum free area of the opening is 1 square inch for each 3000
Btu/hr (700 mm
than the sum of the areas of all vent connectors in the room.
2 /kW) of total boiler input is required.
/kW) of total boiler input is required.
2
INDOOR AIR SUPPLY
DIFF FLOORS ONE OPENING
2000 4000
3000 6000
4000 8000
NFPA 54/ANSI Z223.1 & NFPA/ANSI 211
3 /kW) of installed appliance input capacity.
When rooms are on the same floor, each opening shall have an area
•
equal to 1 square inch for each 1000 Btu/hr (2200 mm
appliance input capacity, but not less than 100 square inches. One
opening should commence less than 12 inches above the floor and the
other less than 12 inches below the ceiling. The minimum dimension of air
openings shall be 3 inches.
When rooms are on different floors, each opening shall have an area
•
equal to 2 square inches for each 1000 Btu/hr (4400 mm
appliance input capacity.
2 /kW) of installed appliance input capacity, and not less
AIR SOURCE
OUTDOOR AIR SUPPLY
DIRECT
667
1000
1334
21
)
TWO OPENINGS
VERT DUCT
500 500
750 750
1000 1000
Gas Fired Boiler
per 1000 Btu/hr
3
/kW) of installed
2
2 /kW) of installed
HORIZ DUCT
1000
1500
2000