Chimney & Vent Pipe Connections - Smith Cast Iron Boilers Series 28A Installation And Operating Instructions Manual

Page 4
All Air From Inside The Building
If the boiler is to be located in a confined space mini-
mum clearances of 24 in, 610 mm must be maintained
between the boiler and any adjacent construction. When
installed in a confined space, two permanent openings
communicating with an additional room(s) are required.
The combined volume of these spaces must have
sufficient volume to meet the criteria for an unconfined
space. The total air requirements of all fuel burning
equipment or any type of exhaust fan must be
considered when making this determination.
Each opening must have a minimum free area of 1 in
1000 Btu/hr, 140 in2/GPH, 2200 mm
total input rating of ALL fuel burning equipment in the
confined area. Each opening must be no less than 100
in 2 , 64,516 mm 2 in size. The upper opening must be
within 12 in, 305 mm of, but not less than 3 in, 76 mm
from, the top of the enclosure.
The bottom opening must be within 12 in, 305 mm of,
but not less than 3 in, 76 mm from, the bottom of the
enclosure.
All Air From Outside The Building
When installed in a confined space Two permanent
openings communicating directly with, or by ducts to,
the outdoors or spaces that freely communicate with the
outdoors must be present. The upper opening must be
within 12 in, 305 mm of, but not less than 3 in, 76 mm
from, the top of the enclosure. The bottom opening must
be within 12 in, 305 mm of, but not less than 3 in,
76 mm from, the bottom of the enclosure.
Where directly communicating with the outdoors or
communicating with the outdoors through vertical ducts,
each opening shall have a minimum free area of 1 in
2
4000 Btu/hr, 35 in /GPH, 550 mm
rating of all of the equipment in the enclosure.
Where communicating with the outdoors through
horizontal ducts, each opening shall have a minimum
free area of 1 in 2 /2000 Btu/hr, 70 in
kW of the total input rating of all of the equipment in
the enclosure. When ducts are used, they must have the
same cross-sectional area as the free area of the
opening to which they connect. When calculating the
free area necessar y to meet the make-up air
requirements of the enclosure, consideration must be
given to the blockage effects of louvers, grills and
screens. Screens must have a minimum mesh size of
1/4 in, 6.4mm . If the free area through a louver or grill
is not known the louver or grill should be sized per Table 1.
SERIES 28A BOILER INSTALLATION AND OPERATION INSTRUCTIONS
2
/kW based on the
2
/kW of the total input
2 /GPH, 1100 mm
Table 1- Make-up Air Louver Sizing
Required Cross Sectional Area (in
Input 1/4" Wire
(MBH) Screen
1000
1200
1400
1600
1800
2000
2200
2 / 2400
2600
2800
3000
3200
3400
3600
3800
4000 1000
4200 1050
4400 1100
4600 1150
4800 1200
CHIMNEY & VENT PIPE
CONNECTIONS
WARNING: The vent installation must be in
accordance with Part 7, Venting of Equipment,
of the National Fuel Gas Code, ANSI Z223.1/
NFPA 54-latest revision, the ASHRAE Equipment
Handbook on Venting or applicable provisions
of the local building codes. Canadian
installations must comply with CAN/CGA B149.1
2 /
or .2 Installation Code. Improper venting of this
boiler can result in excessive levels of carbon
monoxide which can result in severe personal
injury or death!
CAUTION: The products of combustion from a 28A
2 /
must be safely vented to the outdoors while
ensuring that the flue gasses do not cool
prematurely. It's critical that the chimney system be
properly designed to handle the flue gases. An
oversized or uninsulated chimney can cause the
moisture in the flue gases to condense resulting in
damage to the chimney system unless it's
specifically designed for condensate. If this is the
case a suitable condensate drain must be used to
protect the boiler from condensate.
NOTE: Our warranty does not cover corrosion
damage to the boiler or its vent system caused by
flue gas condensate!
Metal
Louvers
75% Free Area
250 333
300 400
350 467
400 533
450 600
500 667
550 733
600 800
650 867
700 934
750 1000
800 1066
850 1134
900 1200
950 1267
1334
1400
1467
1533
1600
2
)
Wooden
Louvers
25% Free Area
1000
1200
1400
1600
1800
2000
2200
2400
2600
2800
3000
3200
3400
3600
3800
4000
4200
4400
4600
4800