LAARS Mighty-Stack TL80-199 - Installation, Operation and Maintenance Instructions - Manual (Page 7)

Mighty Stack Water Heater Page 7
1J. General Venting Instructions
WARNING
This water heater must be vented in accordance
with Part 7, Venting of Equipment, of the latest
edition of the National Fuel Gas code, ANSI Z223.1
and all applicable local building codes. In Canada,
follow CAN/CGA B149 Installation codes. Improper
venting of this appliance can result in excessive
levels of carbon monoxide which can result in
severe personal injury or death!
Here are some general rules to follow when
venting this unit:
• Place the water heater as close as possible to the
vent or chimney.
• The vent collar on the water heater must be
fastened directly to an unobstructed vent pipe.
Use rustproof sheet metal screws no longer than
1/2" (13 mm).
• Do not weld the vent pipe to the water heater
collar. The weight of the stack must not rest on
the water heater. The top of the water heater
must be easily removable for normal service and
inspection of the unit.
• The water heater vent must not be connected to a
fireplace, wood stove or other equipment which
burns solid fuel.
• Avoid terminating the water heater vent near any
air-conditioning or air-supply fans. These fans
can pick up the exhaust flue products from the
water heater and return them to the building.
This can create a health hazard.
• Avoid using an oversized vent pipe or using
extremely long runs of the pipe. This may cause
excessive cooling and condensation of flue
gases.
1K. Vertical Venting – Category I
This unit can be vented into a masonry chimney,
provided several conditions are met (see Figure 6).
• The chimney must have an appropriate tile lining.
The lining should be the correct size, should be
constructed correctly, and must be clean.
• Check the chimney passage way to be sure that it
is clear and free of obstructions.
• If the chimney must be rebuilt, follow nationally-
recognized standards. (See the National Building
Code or ANSI/NFPA 211.)
For installation in U.S.A.:
Water Heater Outside Air Inside Air
Size Area † Area ††
199 50 sq in. 199 sq in.
323 sq cm 1284 sq cm
The area indicated is for one of two openings; one at floor
level and one at ceiling, so the total net free area would be
double the figures indicated. For special conditions, refer to
NFPA54 ANSI Z223.1.
† Outside air supply – Combustion air is supplied directly
through an outside wall.
†† Inside air supply – Combustion air is supplied from inside
the building.
NOTE: Check with louver manufacturers for Net Free Area
of Louvers. Correct for screen resistance to the New Free
Area if a screen is used.
Table 5. Minimum Recommended Air Supply
to Water Heater Room.
Outside Air Supply: When combustion air is
supplied directly through an outside wall, each
opening should have a minimum free area of one
square inch per 4,000 BTUH input of the total input
rating of all appliances in the enclosed area.
Inside Air Supply: When combustion air is
supplied from inside the building, each opening
should have a minimum free area of one square inch
(6.5 sq cm) per 1,000 BTUH input of the total input
rating of all appliances in the enclosed area. These
openings should never be less than 100 square inches
(645 sq cm).
For installation in Canada:
NOTE: In Canada, follow Canadian Standard
CAN/CGA-B149 or local codes.
Exhaust Fans or Vents: Any equipment which
exhausts air from the room around the unit can deplete
the combustion air supply. Such equipment can also
reverse the action of the venting system. This could
cause flue products to accumulate in the space where
the water heater is installed. Additional air must be
supplied to compensate for any exhaust effect.
The information in Table 5 is not applicable in
installations where exhaust fans or blowers of any
type are used. Such installations must be designed by
qualified engineers.
If a blower or fan is used to supply air to the
water heater room, the installer should make sure it
does not create drafts which could cause nuisance
shutdowns. If a blower is necessary to provide
adequate combustion air to the water heater, a switch
or equivalent must be wired into the water heater
control circuit to prevent the water heater from firing
unless the blower is operating.
The water heater must be protected from any
source of corrosive chemical fumes including those
emitted by trichlorethylene, perchlorethylene,
chlorine, etc.