Amtrol OWB Series - Manual (Page 16)

NOTE
All wall openings directly to outdoors must be screened to prevent entry by birds or small
animals.
With Horizontal Ducts See Figure 10.
Note: Each air duct opening
shall have a free area of not
less than one square inch
per 2,000 Btu per hour of the
total input rating of all
equipment in the enclosure.*
Chimney
Outlet Air Duct
Inlet Air Duct
*If the equipment room is located against an outside wall and the air
openings communicate directly with the outdoors, each opening shall have
a free area of not less than one square inch per 4,000 Btu per hour of the
total input rating of all equipment in the enclosure.
Figure 10.
CHIMNEY OR VENT REQUIREMENTS
WARNING
Inspect existing chimney to make sure it is clean, the right size, properly constructed and
in good condition before installing boiler. Failure to do so may cause a hazardous
operating condition.
NOTE
Venting must conform with applicable local codes and for the National Board of Fire
Underwriters.
1. Chimney must be a Class A chimney.
2. This is a high efficiency boiler which operates with a low stack temperature
which may be subject to condensation in a cool or improperly designed chimney.
Accordingly, the right vent or liner is very important.
a) Masonry chimney with three walls exposed to outdoors may require
the use of a 316 stainless steel liner.
b) Masonry chimney with all inside walls—use a tile liner.
16
Installation, Operation, And Service Instructions