5
c. Each of the appliances served shall be
interlocked to the mechanical air supply to
prevent main burner operation when the
mechanical air supply system is not in operation.
d. In buildings where the combustion air is provided
by the mechanical ventilation system, the system
shall provide the specified combustion air rate in
addition to the required ventilation air.
8. Louvers & Grills:
a. The required size of openings for combustion,
ventilation, and dilution air shall be based on the
net free area of each opening.
i. Where the free area through a louver or grille
is known, it shall be used in calculating the
opening size required to provide the free area
specified.
ii. Where the free area through a louver or grille
is not known, it shall be assumed that wooden
louvers will have 25% free area and metal
louvers and grilles will have 75% free area.
iii. Nonmotorized dampers shall be fixed in the
open position.
b. Motorized dampers shall be interlocked with the
equipment so that they are proven in the full
open position prior to ignition and during
operation of the main burner.
i. The interlock shall prevent the main burner
from igniting if the damper fails to open
during burner startup.
ii. The interlock shall shut down the burner if
the damper closes during burner operation.
9. Combustion Air Ducts
a. Ducts shall be constructed of galvanized steel or
an equivalent corrosion- resistant material.
b. Ducts shall terminate in an unobstructed space,
allowing free movement of combustion air to the
appliances.
c. Ducts shall serve a single space.
d. Ducts shall not serve both upper and lower
combustion air openings where both such
openings are used. The separation between ducts
serving upper and lower combustion air
openings shall be maintained to the source of
combustion air.
e. Ducts shall not be screened where terminating in
an attic space.
f. Horizontal upper combustion air ducts shall not
slope downward toward the source of the
combustion air.
g. The remaining space surrounding a chimney
liner, gas vent, special gas vent, or plastic piping
installed within a masonry, metal, or factory built
chimney shall not be used to supply combustion
air.
h. Combustion air intake openings located on the
exterior of buildings shall have the lowest side of
the combustion air intake opening at least 12
inches (305 mm) above grade.
D. INSTALLATION SURVEY
For new and existing installations, a Water Installation
Survey is available from PB Heat, LLC. The survey will
provide information on how a hot water boiler works
with your specific system and will provide an overview
of hot water system operation in general.
You can also use this survey to locate system problems
which will have to be corrected. To obtain copies of the
Water Installation Survey, contact your PB Heat
representative or download it from PeerlessBoilers.com.
E. PLANNING THE LAYOUT
Prepare sketches and notes of the layout to minimize the
possibility of interferences with new or existing
equipment, piping, venting and wiring.
Liquefied Petroleum (LP) is heavier than air and may
collect or “pool” in a low area in the event of a leak
from defective equipment. This gas may then ignite,
resulting in a fire or explosion.
WARNING
PREINSTALLATION