General Venting Guidelines; Venting Options; Vertical/Chimney Venting - RBI LCD Series Installation & Operation Manual

GENERAL VENTING GUIDELINES

WARNING: The vent installation must be in
accordance with Part 7, Venting of Equipment,
of the National Fuel Gas Code, ANSI Z223.1/
NFPA 54-latest revision or applicable provisions
of the local building codes. Canadian
installations must comply with CSA B149.1 or
.2 Installation Code. Improper venting can result
in excessive levels of carbon monoxide which
can result in severe personal injury or death!
All vent systems must be fully supported by the building
structure and not by the boiler/water heater. Appropriate
thimbles and fire-stops must be used where required.
WARNING: Common vent systems must be
properly engineered and sized to provide a
negative draft of 0.01 to 0.08 in, .25 to 2.0 mm
W.C. at the flue outlet! Common positive
pressure vent systems are not to be used.
Improper installation can result in excessive
levels of carbon monoxide which can cause
severe personal injury or death!
NOTE: A double acting barometric damper must be
installed directly to the boiler/water heater flue
outlet to ensure proper operation. This does not
apply to outdoor units or direct vent positive
pressure units.
VENT SYSTEM OPTIONS
The LCD may be vented the following ways:
1) Vertical/Chimney Venting - uses an approved metal
chimney system or properly lined masonry chimney.
Combustion air is obtained from the space in which the
unit is installed or from outdoors. A double acting
barometric damper must be installed near the flue outlet
when venting vertically. See Figures 6 and 7. This also
applies to any fan-assisted chimneys or vents.
2) Direct Vent, Positive Pressure - for horizontal vent
runs equivalent to 35 ft, 10.8 m or less. A stainless steel
vent system certified to UL 1738 for installations in the
United States. ULS636 for installations in Canada must
be used when combustion air is ducted from outdoors,
from the same wall.
3) Horizontal Vent, Negative Pressure - for horizontal
vent runs equivalent to more than 35 ft, 10.8 m (90
degree elbow equals 10 equivalent feet). A dedicated
wall mounted power venter must be used. The vent
system can be single wall galvanized steel or type B
vent pipe. Combustion air is obtained from the space in
which the unit is installed or from the outdoors.
LCD INSTALLATION AND OPERATION INSTRUCTIONS
A barometric damper must be installed when the
horzontal run is longer than 35 equivalent feet. (90 degree
elbow = 10 equivalent feet). If this is the case, a power
venter must also be used.
If horizontal run is less than 35 equivalent feet, do not
use a barometric damper. Follow applicable instructions
under the "COMBUSTION AIR & VENTILATION" section.
4) Outdoor Installation - uses the outdoor option kit.
Barometric damper is not required.
NOTE: All venting, combusiton air material supplied
by installer.

VERTICAL/CHIMNEY VENTING

The LCD is listed as a Category I appliance when
vented vertically into a metal chimney system or
properly sized masonry chimney, Figures 1,2, 6 & 7. The
chimney must provide a negative pressure of 0.01 to
0.08 in, .25 to 2.0 mm W.C. at the boiler/water heater
flue collar with the unit running at full load. A barometric
damper must be installed between the flue collar and
the vent connector. Approved thimbles and fire-stops
must be used when combustible construction is
penetrated.
WARNING : If an appliance using any type of a
mechanical draft system operating under
positive pressure is connected to a chimney
flue, never connect any other appliances to this
flue. Doing so can result in excessive levels of
carbon monoxide which can cause severe
personal injury or death!
Chimney Inspection & Sizing
A thorough inspection of the masonry chimney must be
performed to ensure that the chimney is clean, properly
constructed, lined and sized. Exterior masonry chimneys
should not be used unless properly lined to prevent
condensation and draft problems. Table 4 lists the
equivalent breeching and flue sizes required for the
boiler/water heater. When more than one appliance is
connected to the same chimney flue the flue must be
large enough to safely vent the combined output of all
of the appliances.
Table 4 - Equivalent Breeching & Chimney Size
Model Size
225
300 - 400
600 - 750
900 - 1050
1200 - 1480
1650 - 2300
Note: These sizes are based on a 20 ft, 6.1m chimney height.
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Pipe Diameter
mm
in
5 127
6 152
8 203
254
10
12 305
14 356