Modulex EXT Vent and Combustion Air Application Guide
TAG-0054_0F
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page 9 of
28
GF-136–V
Phone: 800-526-0288
09/25/2017
CHAPTER 2:
COMBUSTION AIR SYSTEM
WARNING!
Air openings to combustion area must not be obstructed. Using Table 2, air openings may be
specified so that adequate combustion air can be maintained.
2.1.
COMBUSTION AIR REQUIREMENTS
WARNING!
•
Non-Motorized louvers and grilles must be fixed in an open position.
•
Minimum screens mesh size shall not be smaller than 1/4” (inch) mesh.
Table 2, below, shows the minimum required air openings in square inches (square centimeters) freely
communicating with the outdoors for boiler room combustion and ventilation air for each boiler. For
multiple boiler installations, sum the openings for the specific boiler sizes.
TABLE 2: Min. Required Air Openings Freely Communicating With the
Outdoors for Boiler Room Combustion & Ventilation Air
MODEL
TWO SEALED
COMBUSTION OR
VERTICAL DUCTS EACH
HAVING AN OPENING IN
SQ. IN. (SQ.CM) OF:
TWO HORIZONTAL
DUCTS EACH HAVING AN
OPENING IN SQUARE
INCHES OF:
SINGLE
PERMANENT
OPENING
EXT 321
80 in
2
(516 cm
2
)
161 in
2
(1039 cm
2
)
107 in
2
(690 cm
2
)
EXT 481/450
120 in
2
(774 cm
2
)
241 in
2
(1555 cm
2
)
160 in
2
(1032 cm
2
)
EXT 641/600
160 in
2
(1032 cm
2
)
321 in
2
(2071 cm
2
)
214 in
2
(1381 cm
2
)
EXT 802/800
201 in
2
(1297 cm
2
)
401 in
2
(2587 cm
2
)
267 in
2
(1723 cm
2
)
EXT 962
241 in
2
(1655 cm
2
)
481 in
2
(3103 cm
2
)
321 in
2
(2071 cm
2
)
EXT 1123/1100
281 in
2
(1813 cm
2
)
562 in
2
(3626 cm
2
)
374 in
2
(2413 cm
2
)
EXT 1530/1500
383 in
2
(2471 cm
2
)
765 in
2
(4935 cm
2
)
510 in
2
(3290 cm
2
)
EXT 1912
478 in
2
(3084 cm
2
)
956 in
2
(6168 cm
2
)
637 in
2
(4110 cm
2
)
EXT 2295/2300
574 in
2
(3703 cm
2
)
1148 in
2
(7406 cm
2
)
765 in
2
(4935 cm
2
)
EXT 2677/2600
669 in
2
(4316 cm
2
)
1339 in
2
(8639 cm
2
)
892 in
2
(5755 cm
2
)
EXT 3060/3000
765 in
2
(4936 cm
2
)
1530 in
2
(9871 cm
2
)
1020 in
2
(6581 cm
2
)
1. The combustion air must be free of chlorine, halogenated hydrocarbons or other chemicals that
can become hazardous when used in gas-fired equipment. Common sources of these
compounds are swimming pools, degreasing compounds, plastic processing, and refrigerants.
Whenever the environment contains these types of chemicals, combustion air MUST be
supplied from a clean area outdoors for the protection and longevity of the equipment and
warranty validation.
2. Ventilation of the boiler room must be adequate enough to provide sufficient air to properly
support combustion.