5
Combustion Air
Provide combustion and ventilation air in accordance
with the section “Air for Combustion and Ventilation”, of
the National Fuel Gas Code, ANSI Z223.1/NFPA 54, or
applicable provisions of the local building codes.
Chimney And Vent Pipe Connection
This is a very important part of the heating system. It must
be clean, the right size, properly constructed and in Good
Condition. No boiler can function properly with a bad
chimney. See Pages 6-10 for specifi c venting instructions.
Flue pipe should be same size as draft hood outlet from boiler
to fl ue collector. See Chart 1 for Typical Chimney Size. Main-
tain a minimum upward slope of 1/4 inch per linear foot from
boiler to the chimney. Fasten joints together with sheet metal
screws to prevent sagging.
Boiler Location
Locate boiler on level, non-combustible foundation as near
to chimney or fl ue as possible. Allow 24 inches at front and
sides of boiler for servicing and cleaning. When installed in
utility room, the door should be wide enough to allow the
largest boiler parts to enter, or permit replacement of any
other appliance in the same room.
Installing contractor must provide ventilated
foundation for boiler when installing:
• Over a room
• Over electrical wiring or cables of any kind
• If concrete fl oor is “green,” or water is channeled
under concrete fl oor
Minimum Vent Pipe Clearance
If the vent pipe must go through a crawl space, double
wall vent pipe should be used. Where vent passes through
a combustible wall or partition, use a ventilated metal
thimble. The thimble should be 4 inches larger in diameter
than vent pipe. If boiler is installed with single wall
galvanized type vent pipe, it must have 6 inches clearance
between its surface and any combustible material. If
UL listed type B (insulated) vent pipe is used, clearance
between it and combustible material to be as listed by pipe
manufacturer.
FOR INSTALLATION ON NON-COMBUSTIBLE
FLOORS ONLY,
MINIMUM CLEARANCES TO
COMBUSTIBLE CONSTRUCTION
Inputs of
400 MBH or
less
Inputs over
400 MBH
Top
52”
52”
Front
Alcove
Alcove
Flue Collector
6 “
6”
Rear
18”
24”
Sides
18”
24”
Steam/Water
Piping
1”
1”
Greater clearances (24”) for access should supersede
fi re protection clearances.
BEFORE INSTALLING
