LCD Series Finned Copper Tube Gas Boilers & Water Heaters – Boiler Manual
9
GENERAL VENTING GUIDELINES
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. See Figure A for added clarity.
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.
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
WC 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!
Multi-story, common venting systems shall be in
accordance with the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 and/or the CSA B149.1, Natural
Gas and Propane Installation Code (Current Editions),
local codes and vent manufacturer's installation
instructions. Size the chimney and breeching using
generally accepted engineering practices. (Consult
factory for vertical heights beyond 60 ft.)
A single 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.
Some venting applications may require the stop to be
removed for smooth operation. The barometric
damper should be located after the flue collector, refer
to Figures 2, 7A and 8 for proper location. Carefully
follow the instructions provided with the barometric
damper. Check with local codes for specific
requirements.
In Canada, B149 (7.25 Draft Regulators) states the
damper shall be of double-acting type.
To avoid spillage into the room of dangerous flue gas
containing carbon monoxide, the opening in damper
must never face against the flow of flue gas.
Boiler/Water Heater shall not be connected to a
chimney flue serving a separate appliance designed
to burn solid fuel.
VENT SYSTEM OPTIONS
The LCD may be vented the following ways:
1)
Vertical/Chimney Venting, Negative Pressure, Category
I -
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 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, Category III -
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. ULC S636 for
installations in Canada must be used when combustion air is
ducted from outdoors, from the same wall.
3)
Horizontal Vent, Negative Pressure, Category I -
for horizontal vent runs equivalent to more than
35 ft,
10.8 m
(90° elbow equals 10 equivalent ft). 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.
A barometric damper must be installed when the horzontal run
is longer than 35 equivalent feet. (90° elbow = 10 equivalent
ft). If this is the case, a power venter must also be used.
4)
Outdoor Installation -
uses the outdoor option kit. Barometric
damper is not required.
All venting, combusiton air material supplied by
installer. All venting material must be approved for the
application. Consult the vent manufacturer’s product
literature.
