Lochinvar Power-Fin PF 1500, Руководство дизайнера

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L o c h i n v a r
D E S I G N E R
’
S G U I D E P O W E R
-
F I N W A T E R H E A T E R
6 1 5 - 8 8 9 - 8 9 0 0
5
COMBUSTION &
VENTILATION AIR
Provisions for combustion and ventilation air
must be in accordance with Section 5.3,
Air For Combustion And Ventilation, of the
latest edition of the
National Fuel Gas Code
ANSI Z223.1, or applicable provisions of
the local building codes.
If air is taken directly from outside the
building with no duct (FIG. 3):
A. Combustion air opening, one square
inch per 4000 Btu/hr input. This opening
must be located within 12” of the
bottom of the enclosure.
B. Ventilation air opening, one square
inch per 4000 Btu/hr input. This opening
must be located within 12” of the top of
the enclosure.
If air is taken from another interior space
(FIG. 4), each opening specified above
should have a net free area of one square
inch for each 1000 Btu/hr input.
If combustion and ventilation air is taken
from the outdoors using a duct to deliver
the air to the mechanical room (FIG. 5),
each opening should have a net free
area of one square inch per 2000
Btu/hr input.
If a single combustion air opening is
provided to bring combustion air in
directly from the outdoors (FIG. 6), the
opening should have a net free area of
one square inch per 3000 Btu/hr input.
This opening must be located under 12”
of the top of the enclosure.
(FIG. 3) COMBUSTION AIR DIRECT FROM OUTSIDE
(FIG. 6) COMBUSTION AIR DIRECT FROM OUTSIDE
SINGLE OPENING
(FIG. 5) COMBUSTION AIR THROUGH DUCTWORK
(FIG. 4) COMBUSTION AIR FROM AN INTERIOR SPACE
1.
2.
3.
4.
CAUTION: Under no circumstances
should the equipment room be under a
negative pressure, when atmospheric
combustion equipment is installed in the
room.
EXAMPLE OF
SIZING FOR
COMBUSTION
& VENTILATION
AIR OPENINGS
(UNIT WITH
1,000,000
Btu/hr INPUT):
When combustion and
ventilation air is taken
from directly outside the
building (FIG. 3), divide
the total Btu/hr by
4,000. This yields 250
sq.in. of “Free Area”
without restriction.
1,000,000 ÷ 4,000 =
250 sq.in.
Since the air opening is
50% closed due to
screens and louvers, the
total opening must be
multiplied by 2.
250 sq.in. x 2 =
500 sq.in.
This project requires one
Ventilation Air Opening
with a net “Area” of
500 square inches with
louver dimensions of
20” x 25” and one
Combustion Air Opening
with a net “Area” of
500 square inches with
louver dimensions of
20” x 25”.