Horizontal Venting - RBI LCD Series Installation & Operation Manual

Page 10
Vent Connections
Locate the boiler/water heater as close to the chimney
as possible. Use the shortest, straightest vent connector
possible for the installation. If horizontal runs exceed
5 ft, 1.5 m they must be supported at 3 ft, 0.9 m
intervals with overhead hangers. Use a type B, single
wall stainless or single wall galvanized steel vent pipe
the same diameter as the flue collar to connect the
boiler/water heater to a masonry chimney. When using
an approved metal chimney system use the appropriate
vent connector. The vent connector should be sloped up
toward the chimney at a minimum rate of 1/4 in/ft,
2 cm/m . On masonry chimneys the connector must
terminate flush with the inside of the chimney flue,
Figure 2. Fasten each single wall vent connection with
at least 3 corrosion resistant sheet metal screws.
WARNING: Never install a vent pipe having a
diameter different than that of the boiler/water
heater flue collar. Failure to comply with this
warning can result in excessive levels of carbon
monoxide which can cause severe personal
injury or death.
Always provide a minimum clearance of 6 in, 152 mm
between single wall vent pipe and any combustible
materials. Type B1 vent may be used, clearance between
it and any combustible material must be as listed.
WARNING: Failure to maintain minimum
clearances between vent connectors and any
combustible material can result in a fire causing
extensive property damage, severe personal
injury or death!
DIRECT VENT,
POSITIVE PRESSURE
In this configuration the boiler/water heater blower is
used to push the flue products to the outdoors while
drawing combustion air from the outdoors. The equivalent
length of the vent and combustion air systems must not
exceed 35 ft, 10.8 m for each. The Intake Air Option
instructions under the "COMBUSTION AIR &
VENTILATION SECTION" must be followed! The vent
system must be sized per Table 4.
LCD INSTALLATION AND OPERATION INSTRUCTIONS
Horizontal Direct Vent Systems - Figures 4 & 5
The vent materials used in horizontal vent systems
must be certified to UL 1738 for installations in the
United States, ULS636 for installations in Canada. The
certified vent terminal from RBI must also be used. The
following manufactures have systems that meet these
requirements:
Heat-Fab, Inc.
38 Hayward Street
Greenfield, MA 01301, (800) 772-0739.
Z-Flex U.S., Inc.,
20 Commerce Park North
Bedford, NH 03110-6911, (800) 654-5600.
Protech Systems Inc.
26 Gansevoort Street
Albany, NY 12202, (518) 463-7284
The maximum equivalent length for the horizontal vent
and combustion air pipes is 35 ft, 10.8 m for each.
Each 90˚ elbow and the intake air and vent terminals
are equal to 10 ft, 3.3 m of straight pipe. To maximize
the performance of single wall sheet metal vent systems
locate 90˚ elbows as far from the boiler as possible and
from one another. For best results, horizontal vent
systems should be as straight as possible.
The vent system must be both gas tight and watertight.
All seams and joints in metal pipes must be joined
and sealed in accordance with the vent system
manufacturer's instructions.
When horizontal vent runs exceed 5 ft, 1.5 m they
must be supported at 3 ft, 0.98 m intervals with
overhead hangers. The vent system must be pitched
down, toward the vent terminal, 1/4 in/ft, 21 mm/m .
If any part of a single wall metal vent system passes
through an unheated space it must be insulated with
insulation rated for 400˚F, 204˚C .