Weil-McLain 78 - Manual (Page 3)

• Installation • Start-Up • Maintenance • Parts
Before Installing Boiler
1a
Installation must comply with:
• State, provincial and local plumbing,
heating and electrical codes.
• Regulations of serving utilities.
• National codes where applicable.
Before selecting boiler location:
• Check for nearby connections to:
– fuel supply
– electrical power
– system water or steam piping
– venting systems - see page 23
– combustion and ventilation air supply - see
“Provide combustion and ventilation air
supply openings” below
• Check area around boiler for and remove any
combustible materials, gasoline and other
flammable vapors and liquids.
Failure to keep boiler area clear and free of
combustible materials, gasoline and other
flammable liquids and vapors can result in severe
personal injury, death and substantial property
damage.
Provide combustion and ventilation
air openings:
Do not install an exhaust fan in boiler room.
Adequate combustion and ventilation air must be
provided to assure proper combustion and
prevent possibility of flue gas leakage and carbon
monoxide emissions, causing severe personal
injury or death.
Opening sizes must comply with state, provincial
or local codes. In their absence, use the following
when boiler is in a confined room:
• Provide two permanent openings in boiler
room - one within 12 inches of ceiling, one
within 12 inches of floor. Minimum dimension
of each opening - 3 inches.
- When all air is taken from within building,
each opening should be at least one square
inch/1,000 Btuh boiler input and freely
connect with areas having adequate
infiltration from outside
- When all air is taken from outdoors, each
opening should connect directly or by ducts
from outdoors or crawl or attic spaces that
freely connect with outdoors and sized as
listed below:
- through outside wall or vertical ducts - at
least one square inch/4,000 Btuh boiler
input
- through horizontal ducts - at least one
square inch/2,000 Btuh boiler input
- where ducts are used, they should be same
cross-sectional area as free area of
openings they are connected to
- compensate for louver, grille or screen
blockage when calculating free air
openings. Refer to their manufacturer’s
instructions for size. If unknown, use:
- wood louvers - 20-25% free air
- metal louvers or grilles - 60-75% free air
- screens - not less than 1/4 inch mesh
Lock louvers in open position, or interlock
with equipment to prove open before
boiler operation.
Part No. 550-141-705 3
Figure 1 Combustion and Ventilation Air
Openings Boiler Room Below Grade
Figure 2 Combustion and Ventilation Air
Openings Boiler Room Partially or Completely
Above Grade
GRADE
GRADE
Grating – Min.
12" above avg.
snowline
Louver – Min.
12" above avg.
snowline
Note:
Duct size
equal to total
louver area
Areaway
Louver
Boiler room
floor
Boiler room
floor
Note:
Size of areaway
and grating to be
equal to or
greater than total
louver area.