Installation manual

Page 13
6. Intake Venting
1. Be certain adequate air is available for combustion and ventilation.
a.) Boiler located in unconfined space:
Installation in large areas, such as basements, can usually be assumed to
provide sufficient air.
b.) Boiler located in confined space :
(See Figure A.)
If all air for combustion and ventilation is to come from within the building:
Two (2) openings shall be provided with one (1) opening commencing within
12 inches of the ceiling and one (1) opening commencing within 12 inches of
the floor of the enclosure. These openings shall not be located closer than 3
inches from either the top or bottom of the enclosure and shall be open to
areas connecting freely with the outdoors. The area of each opening shall
not be less than one square inch per 1000 BTU/HR. of total input rating of all
appliances within the enclosure; with a minimum of 100 square inches for
each opening.
If all the air for combustion and ventilation is to come from outside the
building: Two (2) openings shall be provided with one opening commencing
within 12 inches of the top and an opening commencing within 12 inches of
the bottom of the enclosure. These openings shall not be located closer than
3 inches from either the top or bottom of the enclosure, and shall connect
directly or by ducts with the outdoors. The area of each opening shall be
equal to one square inch per 4000 BTU/HR of total input rating. If ducts are
used to convey the air, vertical ducts require areas of one square inch per
4000 BTU/hr. Horizontal ducts require one square inch per 2000 BTU/hr.
Ducts shall have the same cross sectional area as the full area of the louver
openings.
The upper opening is essential for maintenance of proper air
circulation with the boiler and of reasonable ambient temperature to maintain
proper control temperatures. When a duct is used for ventilation, check for
louver free net area and correct for screen resistance to ensure that the
sufficient ventilation area has been satisfied. DO NOT INSTALL THE
BOILER UNTIL PROPER COMBUSTION AIR HAS BEEN ARRANGED.