Installation Instructions; Air Requirements - Bosch WR 400-3.K Série Mode D'emploi

FORWARD
The design of the WR400-3.K.. complies with CAN 1-4.3
and ANSI Z21. 1 0 (latest edition) as an instantaneous gas
water heater. In addition, the WR400-3.K.. also complies
with CAN 1-2. 1 7 for use at high altitudes, 2.000 – 4.500 ft.
above sea level.
Installation, operation and maintenance information are pro-
vided in this manual. Installation and operation instructions
should be thoroughly reviewed before proceeding with in-
stallation of the BOSCH instantaneous gas water heater.

INSTALLATION INSTRUCTIONS

Note: Proper plumbing, venting, gas connections and an
adequate supply of combustion air are required for
safe and reliable operation. Ability equivalent to that
of a licensed tradesman in the field involved is required
for installation and/or servicing of these water heaters.
LOCATION
Before installing the BOSCH instantaneous gas water
heater consideration must be given to proper location.
The location should be as close to a chimney or gas vent as
practicable, in an area with an adequate air supply and as
centralized with the piping system as possible. The heater
should not be located in an area where it will be subject to
freezing. The heater should be located in an area where
leakage of the heater or its connections will not result in
damage to the area adjacent to the heater or to lower floors
of the structure.
Note: When such locations cannot be avoided, it is
recommended that a suitable drain pan, adequately
drained, be installed under the water heater. The pan
must not restrict combustion air flow.
The BOSCH instantaneous gas water heater is designed to
operate on natural or propane gas; however, make sure that
gas on which heater is to operate is the same as specified
on the heater's model/rating plate.
In addition to these instrutions,the water heater shall be
installed in accordance with CAN/CGA-B149 Installation
Code (in Canada) or Z223-1- latest edition, National Fuel
Gas Code (in U.S.A.) and/or local installation Code. These
shall be carefully followed in all cases.

AIR REQUIREMENTS

For safe operation, sufficient air for combustion, ventilation
and dilution of flue gases must be available. An insufficient
supply of air will result in a yellow luminous burner flame,
causing carboning or sooting of the heat exchanger.
In order to prevent corrosion, make sure that the combustion
air is kept free of aggressive substances. Substances that
specially contribute to corrosion are halogenated
hydrocarbons (e.g. chlorine and fluorine), which are
contained in solvents, paint, adhesives, propellant gases,
various household cleaners, etc. Take precautionary
measures as necessary.
In unconfined spaces, in buildings of normal construction,
infiltration normally is adequate to provide air for combustion,
ventilation and dilution of flue gases.
However, a confined space must be provided with two
permanent openings to provide combustion and ventilation
air to the appliance. Each opening shall have a free area of
one square inch per 1000 BTU/Hr* of total input rating of
all appliances in the enclosure. One opening shall be within
12 inches of the top and one within 12 inches of the bottom
of the enclosure.
* SPECIAL NOTE
When the WR400-3.K.. is installed in a confined space of
minimum size the openings described above must be
increased to a size of 1½ square inches per 1000 BTU/Hr.
In other words, when installed in a minimum sized confined
space the two openings that are to be made in the enclosure
within 12 inches of the top and 12 inches of the bottom
must each have a minimum free area of, (1½") x (117)=
175.5 square inches.
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