Bosch W 325 K**T1 Owner's manual

6 720 601 783 CA (03.11) AL
Instantaneous gas water heater
Models
W 325 K..T1
W 400 K..T2
· Installation
· Operation
· Maintenance
The Bosch instantaneous water heater is a high efficiency,
space saving answer to your water heating needs. All Bosch
instantaneous water heaters heat water only as required;
noenergy is lost maintaining a large voluma of water at
elevated temperatures as in tanktype storage water heaters.
Suitable for heating potable water. ertified for space heating
in combination with potable water only. Not certified for
heating only.
W RNING: If the information in this manual is
not followed exactly, a fire or explosion may
result causing property damage, personal injury
or death.
Note: In case of problems please contact your salesman or installer
STR V N DISTRIBUTORS, LTD.
123 harles Street
North Vancouver, B. . V7H 1S1
Phone anada: [phone]
Phone USA: [phone]
Web Site: www.astravan.com
RE D INSTRUCTIONS C REFULLY BEFORE INST LLING
NOTICE TO INST LLER: Please leave this manual
with the owner or affix adjacent to appliance.
−−
−−
−Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
−−
−−
−WH T TO DO IF YOU SMELL G S
••
••
•Do not try to light any appliance.
••
••
•Do not touch any electrical switch; do not use
any phone in your building.
••
••
•Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
••
••
•If you cannot reach your gas supplier, call the
fire department.
−−
−−
−Installation and service must be performed by a
qualified installer agency or the gas supplier.

2
DIMENSIONS
Figure 1
Maximum hydrostatic water pressure – 1.03 Mpa (150 p.s.i.)
Maximum recommend working pressure – 0.69 Mpa (100 p.s.i.)
Minimum working pressure – 0.0138 Mpa (2 p.s.i.) at 2 Litres/min. (0.5 U.S. Gallons/min) free discharge
Minimum recommended inlet water pressure for use with showers 30 p.s.i.g.
* The wall bracket is only required for the WR 325 K … when mounted directly to combustible construction. The WR
400 K… T2 may be mounted directly to combustible construction.
** The high altitude ratings listed are anadian Gas Association high altitude ratings and are only valid in anada. In the
U.S., the National Fuel Gas ode, ANSI Z223.1/NFPA 54, recommends for high altitude installations above 2,000 feet,
that the input rate be reduced 4% for each 1,000 feet above sea level. – See page 8.
Dimensions in Milimetres (inches)
Size, mm Qt.
standard 29.30kW (100,000Btu/hr) 1.25 diam. 14
(0 - 2,000 ft.) 27.83 kW (95,000Btu/hr)
Propane 0.79 diam. 14
high** 26.37kW (90,000Btu/hr) 1.25 diam. 14
(2,000 - 4,500 ft.) 25.05 kW (85,000Btu/hr)
Propane 0.79 diam. 14
standard 34.28 kW 1.25 diam. 16
(0 - 2,000 ft.) (117,000Btu/hr)
Propane 0.82 diam. 16
high** 30.85 kW 1.25 diam. 16
(2,000 - 4,500 ft.) ( 105,000Btu/hr)
Propane 0.82 diam. 16
W400 Natural
W400 Natural
Main Burner orifices
W325 Natural
W325 Natural
Model Type of gas ltitude Input
Model B C D E F G H
400 755 250 155 85 130 410 320
17 1/4" 29 3/4" 9 3/4" 6" 3 1/4" 5" 16 1/8" 12 5/8"
440 770 250 155 85 130 410 320
17 1/4" 30 1/4" 9 3/4" 6" 3 1/4" 5" 16 1/8" 12 5/8"
W325
W400

3
FORW RD
This design complies with AN1-4.3-77 and ANS1Z21.10.3b
1994 as an instantaneous gas water heater. In addition the
unit complies with AN1-2.17-M80 for use at high altitude,
2.000-4.500 feet above sea level.
Installation, operation and maintenance information is
provided in this manual. Installation and operation instrution
should be thoroughly reviewed before proceeding with
installation of the BOS H instantaneous gas water heater.
The BOS H instantaneous gas water heater is designedto
operate on natural or propane gas; however, make sure
that gas onwhich heater is to operate is to operate is the
same as specified on the heater’s model/rating plate.
In addition to these instructions, the water heater shall be
installed in accordance with AN1-B149 Installation ode
(in anada) or ANSI Z223-1/NFFA 54 National fuel Gas
ode (in U.S.) and/or local installation codes.
These shall be carefully folowed in all cases.
INST LL TION INSTRUCTIONS
Note: Proper plumbling, venting, gas connections and an
adequate supply of combustion air are required for safe and
reliable operatrion. Ability equivalent to that of a licensed
tradesman in the field involved is required for installation
and/or servicing of these heaters.
LOC TION
Before installation the BOS H instantaneous gas water
heater consideration must be given to proper location.
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 not be located in 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.
In order to prevent corrosion, make sure that the combustion
air kept free of aggressive substances. Subtances that
especially contribute to corrosion are halogenated
hydrocarbons (e.g. chlorine and fluorine), which are
contained in solvents, paint, adhesives, propellant gases,
various house hold cleaners, etc. Take precautionary
measures as necessary.
If plastic pipes are used , a 1.5 m metal connection must be
provided on the cold and hot sides.
Note: When such loctions 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.
IR 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 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 os all appliances in the
enlosure.One opening shall be within 12 inches of the top
and one within 12 inches of the bottom of the enclosure.
* SPECI L NOTE
When the W 400 K… T2 is installed in a confined space of
minimum size the openings described above must be
increased to a size of 1 ½ square inches per 1000 BTU/Hr.
In other words, for the W400 K..T2 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, (11/
2”) x (117) = 175.5 square inches.

4
For either confined or unconfined space in a building of
tight construction with inadequate infiltration, air must be
drawn from the outdoors or from spaces that freely
communicate the outdoors. Two permanent openings located
as indicated above are to be provided as follows:
1. When communicating with outdoor directly, or by means
of vertical ducts, each opening shall have a free area
of not less than one square inch per 4000 BTU/Hr of
total input of all appliances in the space.
2. When communicating with outdoors by means of
horizontal ducts, each opening shall have a free area of
not less than one square inch per 2000 BTU/Hr of
total input of all appliances in the space.
For detailed reqirements see
- in anada, AN 1-B 149 Installation odes
- in U.S., ANSI Z223.1/NFPA 54 National Fuel Gas ode.
WARNING
1. Flammable materials, gasoline, pressurized containers,
or any other items or articles that are potentially fire
hazards must never be placed on or adjacant to the
heater. The appliance area must be kept free of all
combustible materials, gasoline and other flammable
vapors and liquids.
2. Do not obstruct the flow of combuston and ventilation
air to the appliance.
LEAREN E
In anada
The W 325 and the W 400 are design certified for installation
on a combustible wall (for the W 325 the wall bracket
supplied with the unit must be used for mounting to
combustible construction), and for installation in an alcove
or closet with minimum clearances to 0 mm from back, 102
mm (4 inches) from sides, 305 mm (12 inches) from top and
bottom, and 102 mm (4 inches) from front. A minimum of
305 mm (12 inches) shall be allowed for maintenance of
serviceable parts.
learence from vent is dependant upon the clearence rating
of the venting material used; that is, type B-1 vent is approved
for 1 inch clearence, B-2 vent for 2 inch, etc.
In United States
The W 325 and the W 400 are design certified for installation
on a combustible wall (for the W 325 the wall bracket
supplied with the unit must be used for mounting to
combustible construction), and for installation in an alcove
with minimum clearences to combustible construction of 0
mm from back, 102 mm (4 inches) from sides, 305 mm (12
inches) from top and bottom. In addition, the WR 325 has
also been design certified for closet installation with minimum
clearences to combustible construction of 0 mm from back,
102 mm (4 inches ) from sides, 305 mm (12 inches) from
top and bottom, and 102 (4 inches) from front. A minimum
of 305 mm (12 inches) shall be allowed for maintenance of
serviceable parts. learence from vent is dependent upon
the clearence rating of the venting material used, that is,
type B-1 vent is approved for 1 inch clearence, B-2 vent for
2 inch, etc.
MOUTING
The W 325 K.. and W 400 K.. are design certified for
mounting to a wall. A wall bracket, see figure 1 is provided
with the W 325 K.. and must be used when the heater
mounted on a combustible wall. Heaters may not be installed
directly on a carpeted wall.
The heater, or the wall bracket, must be mounted to the wall
using appropriate anchoring materials.
W RNING
Failure to use the wall bracket with the W 325 K… when
installing the unit on combustible construction will cause
an unsafe condition and possible fire. In addition, failure to
use the wall bracket when installing the W 325 K… on
combustible construction will be in violation of A.G.A. and
.G.A. certification of the unit.
Note: If wall is a stud wall sheethed with plasterboard it is
recommended that support board(s), either 1 x 4’s or ½
(minimum) plywood first be attached across a pair of
studs and then heater, in the case of the W 400 K…,
or the wall bracket, in the case of the W 325 K…, be
attached to the support boards. See figure 2.
Expansion and contraction of piping due to changing water
temperature in pipes imparts movement to heater which, if
mounted directly to a brittle, friable board such as
plasterboard can cause failure of mounting.
Figure 2
WALL STUDS
WALL
BRA KET
1” X 4” SUPPORT
BOARDS

5
DRIP TR Y
If the water heater is being mounted above a floor of
combustible construction, the drip tray ( shipped loose in
the water heater) must be attached to the bottom of front
cover of the water heater at time of installation. The drip
tray should be attached to the front cover, using screws
provided, as shown in figure 3.
Failure to use drip tray when installing unit above a floor of
combustible construction will cause an unsafe condition and
possible fire and will be in violation of A.G.A. and .G.A.
sertification of the unit.
Figure 3
VENTING
The BOS H instantaneous water heaters have builtin draft
diverters and are designed for indoor installation only. The
draft diverter outlet must be connected to a clear,
unobstructed vent of the same size, or lerger, refer to:
- In anada, AN1-B149 Installation ode for detailed
requirements.
- In U.S.A., ANSI Z223.1/NFPA 54 – National Fuel Gas
ode for detailed requirements.
The flue connection for both the W 325 K… and W 400
K… is 130 mm (5 inches); however, in anada for
installations at high altitude (2,000-4,500 ft. above see level)
a six inch (6”) flue is required for the W 400 K.
5” x 6” adaptor used
on high altitude model
W 400 only
For high altitude use the adaptor must be installed as shown
in figure 4, without alternation, before connecting the six
inch flue to the unit. The adaptor must be secured to the
draft diverter outlet with a minimum of two screws.
Also, in anada, the gas pressure regulator supplied with
the water heater is factory preset to deliver gas to the water
at the proper pressure settting for high altitude operation,
see PRESSURE REGULATION section of this manual.
W RNING
Failure to increase vent size on W 400 to six inches and/or
to assure that manifold pressure is set to proper value listed
on rating plate for applications at altitudes in range 2,000
to 4,500 ft. above sea level will cause unsafe venting,
asphyxiation, and voids .G.A. certification.
W TER CONNECTIONS
The W series instantaneous water heatrs are provided with
two S-bend water connectors/adaptors that must be
connected to inlet and oulet and outlet connections on water
valve assembly, see figure 1 and figure 5 below.
Water valve and S-bends, top view
Figure 5
The purpose of the S-bend water connectors/adaptors is to
provide threaded water connections that meet standards
used in North America, ANSI Standard Taper Pipe Thread
(1/2” NPT). The cold water supply should be connected to
S-bend attached to inlet of water valve and hot water
connection should be made to S-bend attached to outlet of
water valve.
Note: A shut-off valve should be placed in the cold water
supply line to the heater to facilitate servicing the
heater.
Figure 4
DRIP TRAY

6
RELIEF V LVE
The listed pressure relief valve supplied must be installed
near the hot water outlet at time of installation of the heater.
No valve is to be placed between the relief valve and the
heater. A line must be connected to the relief valve to direct
discharge to a safe location. Do not install reducing coupling
or any other restriction in the discharge line must be installed
so as to allow complete drainage of the valve and the line.
See figure 6.
Figure 6
G S CONNECTIONS
Before connecting the gas supply to the heater check
heater’s model/rating plate to make sure that gas on which
heater is to operate is the same as specified on the model/
rating plate.
The W 400 K and the W 325 K instantaneous gas water
heaters are supplied with a gas pressure regulator that must
be installed on the heater before attaching the gas supply
line, see figure 7. Failure to install the pressure regulator, or
the failure to install it in the sequence shown in figure 7 will
be of A.G.A. and .G.A. certification of the unit.
BOS H water heaters are shipped from the factory with
the gas pressure regulators preset for tte gas shown on the
rating plate to the correct pressure:
- in anada, for high altitude operation;
- in U.S., for standard altitude operation unless specially
marked as a high altiude unit.
heck to make sure that the gas listed on the rating plate is
same as gas listed on the pressure regulator.
See PRESSURE REGULATION of this manual for
information regarding gas pressure settings.
Note: Before attaching the gas supply line, be sure that all
gas pipe is clean on the inside. To trap any dirt or
foreign material in the gas suplly line, a drip leg must
be incorporated in the piping. The drip leg must be
readily accessible and not subject to freezing
conditions. Install in accordance with
recommendations of serving gas supplier.
Joint compounds (pipe dope) shall be applied sparingly and
only to the male threads of pipe joints. Do not apply
compound to the first two threads. The joint compound used
must be resistant to the action of liquified petroleum gases.
Before placing water heater in operation check for gas
leakage. Soap and water solution, or other material
acceptable for this purpose, shall be used in locating gas
leaks. Matches, candles, lighters, or other ignition sources
shall not be used for this purpose.
W RNING
The heater and its individual shutoff valve must be
disconnected from the gas supply piping system during any
pressure testing of that system at test pressure in excess of
3,45 kPa (1/2 psig).
The water heater must be isolated from the gas supply piping
system by closing its individual manuaql shutoff valve during
any pressure testing of the gas supply piping system at test
pressures equal to or less than 3.45 kPa (1/2 psig).
The water heater, including the pressure regulator and
manual valve provided with it, must not be operated at gas
supply pressures in excess of 3.45 kPa (1/2 psig). If
overpressure has occurred such as through improper testing
of the gas lines or emergency malfunction of the supply, the
gas valve and regulator must be checked for safe operation.
Make sure that the outside vent valves are protected against
blockage. These are part of the gas supply system, not the
water heater.Vent blockage may occur during ice storms.
Figure 7
PRESSURE TAP
PRESSURE REGULATOR
MANUAL GAS VALVE

7
OPER TING INSTRUTIONS
W RNING
If the water has been damaged or exposed to fire or sooting
or if any part has been underwater do not use. Immediately
call a qualified service technician to inspect the appliance
and to replace any part of the control system and any gas
control which has been underwater and to clean the heat
exchanger assembly and water valve.
FILLING
Before proceeding with operation of the water heater make
sure that system is filled with water.
- Make sure drain is closed, see figure 8, below.
- Open a nearby hot water faucet to permit the water to
fill the heater and piping.
- lose the hot water faucet after the water flows freely
and all air has escaped from system.
- The water heater is now ready to be lit.
Figure 8
SERVICE HINT
The strainer (screen) in the water valve, located in the inlet
of the water valve, may require occasional cleaning due to
foreign material in the water supply. This will restrict the
flow of may affect heater operation and prolong filling time.
To inspect the strainer close the cold water supply valve
ahead of the heater, disconnect S-bend from inlet of water
valve, and remove strainer from inlet. lean if required,
replace strainer in inlet to water valve, reconnect S-bend
and turn on water supply.
Light the water heater in accordance with the instructions
on the Lighting and Operating Plate on the water heater.
For your convenience, the instructions are repeated below.
LIGHTING INSTRUCTIONS
1. STOP! Read the safety information, first section of the
Lighting Instruction Plate on the cover.
2. The main manual gas valve must be closed (turn valve
handle clockwise ) and the gas valve OFF button
depressed . See figure 9.
3. Wait five (5) minutes to clear out any gas. If you then
smell gas, STOP! Follow “B” in the safety information
given above on this plate. If you don’t smell gas, go to
next step.
4. The pilot burner is located behind the peephole located
in the front center of the jacket directlybelow this
instrution plate.
5. Open main manual gas valve by turning valve handle
counterclockwise .
6. Depress PILOT button and light pilot by pushing
PILOT IGNITER button . This may have to be
repeated.
7. Observe pilot flame though peephole. The PILOT button
- should be held down at least 10 seconds with
pilot burning. When the PILOT button is released the
pilot should continue to burn.
- If the PILOT button does not pop up when released
stop and immediately call your service technician or
gas supplier.
- If the pilot will not stay repeat lighting procedure steps
1 through 8.
- If the pilot will not stay lit after several tries, depress the
OFF button , turn the manual gas valve handle
clockwise to OFF position and call your service
technician or gas supplier.
8. Depress the ON button . The heater will now fire
when water is drawn at arate greater than the threshold
flow rate (see manual)*.
Note: If main burner should fail to ignite make sure pilot is
burning. If not repeat lighting procedure steps 1 through 8.
TO TURN OFF G S TO PPLI NCE
1. Depress OFF buton and close the main gas valve
by turning handle clockwise to OFF position. See figure
9.
*see Water Flow Selector section.

8
PRESSURE REGUL TION
The pressure regulator supplied with the water heater is
adjusted to operate on the gas specified on the rating plate,
and:
- in anada, is factory preset to deliver gas at the high
altitude pressure setting listed on the rating plate and
as shown below.
- In the U.S., is factory preset to deliver gas at the standard
altitude setting listed on the rating plate and as shown
below.
The pressure setting of the gas pressure regulator should
be checked at installation to assure that the setting is correct
for the gas being used and the altitude at which the
appliance is installed. See rating plate on the unit, or the
chart below for proper settings.
In anada, for a heater being installed at standard altitude
(o-2,000 ft. elevation) the manifold pressure should be reset
at installation to value shown on the rating plate, or chart
below, for standard altitude.
The gas pressures specified below refer to flow pressure
taken at the pressure tap in the gas inlet pipe (just above
pressure regulator), figure 9, while the heater is operating
at full input.
ppliance Regulator Pressure Setting
*Note: The high altitude ratings listed are anadian Gas
Association high altitude ratings for the appliances and are
only valid in anada. In the U.S. the National Fuel Gas
ode, ANSI Z223.1/NFPA 54, recommends for high altitude
installations, above 2000 feet, that the input rate be reduced
4% for each 1,000 Feet above sea level.
Your appliance dealer and/or your local gas supplier should
be consulted in regard to any high altitude installation. If
field adjustment is required it should be performed by a
qualified serciveman experienced in such work.
TEMPER TURE REGUL TION
I W325K and W400K Models only
For domestic purposes the water flow selector should be
turned clockwise to stop and the gas control slide slid to
right hand stop and remain in those positions.
See figure 10.
Should overheating occur or the gas supply fail to shut
off, turn off the manual gas control valve to the appliance
and have the heater checked by a qualified serviceman to
determine the reason for te malfunction.
Figure 9
PRESSURE TAP
PRESSURE REGULATOR
MANUAL GAS VALVE IN OFF
POSITION
GAS ONTROL SLIDE
WATER FLOW SELE TOR KNOB
W325K AND W400K ONLY
Figure 10
WATER FLOW SELE TION
With the water flow selector turned clockwise to the stop,
the heater’s water valve will regulate the flow rate through
the heater permitting a maximum flow rate of:
- 5.8 L/Min. (1.5 U.S. Gal./min.), for W325
- 6.8 L/Min. (1.8 U.S. Gal./min.), for W400
This setting permits a person at a remote location to control
the water temperature by mixing more or less cold water
with the hot water supplied by the heater.
WATER THROTTLE S REW
W400K5 MODEL ONLY
kPa Inches, W.C.
natural 1.36 5.5 standard
propane 2.61 10.5 (0-2,000 ft.)
natural 1.09 4.4 high *
propane 2.11 8.5 (2,000 - 4,500 ft.)
natural 1.41 5.7 standard
propane 2.61 10.5 (0-2,000 ft.)
natural 1.14 4.6 high *
propane 2.09 8.4 (2,000 - 4,500 ft.)
W325
W325
W400
W400
Model Type of Gas
Pressure
ltitude

9
The water flow selector regulates the hot water output by
adjustng the flow rate of the water through the heater. Below
you will find listed the maximum that can be selected by
adjusting the water flow selector and the minimum flow rate
for main burner operation.
Also listed are the temperature rises that would be expected,
at flow rates indicated, when the heater is firing at full input.
W TER FLOW DJUSTMENT R TE LL
MODELS
*Note: If flow rate through the heater is less than the minimum
flow rate shown for the heater the main burner will not fire.
The minimum flow rate is the “THERSHOLD FLOW RATE”
referred to in the lighting instructions.
II W400 K5 Models only
These models do not have a manual flow selector knob.
Flow can be regulated using the water throttle screw on the
bottom of the water control valve (see fig.8).
Because this model is usually always used for full flow
applications such as recirculation to storage, pressure
washers, boosters, etc., this water throttle screw somes from
the factory srewed in (clockwise) to maximum flow position
to give flows and temperature indicated above.
GAS ONTROL SLIDE
With the gas control slide at the right hand stop the heater
will fire at its full rated input when water is drawn at a rate
that will cause the gas valve to open fully. The gas control
slide will restrict the input down to approximately 50% of
full rated input when adjusted to the left hand stop.
HIGH TEMPERATURE LIMIT SWIT H
The BOS H W series instantaneous gas water heaters
are equipped with a high temperature switch with a set point
of approx. 90° ( 194° F). If the water temperature at the
point exceeds the set point the switch will open, interrupting
the safety circuit and stopping gas flow to the pilot and
main burner.
Outage as a result of high limit operation indicates that the
heater is not functioning properly. The heater should be
checked by a qualifed serviceman and reason for
malfunction corrected. To relight pilot follow instructions
provided on unit.
1
3 L/min.
(
3.4 U.S. Gal./min.) Temp.
Rise 25° C (45° F)
15 L/min. (4.0
U.S. Gal./min.) Temp.
Rise 25° C (45° F)
5.8 L/min. (1.5
U.S. Gal./min.) Temp.
Rise 55° C (100° F)
6.8 L/min. (1.8
U.S. Gal./min.) Temp.
Rise 55° C (100° F)
Maximum Flow Rate
(counter-clockwise to stop)
Model Minimum Flow Rate
(clockwise to stop)
W 325
W 400

10
PREVENTIVE M INTEN NCE
PILOT AND MIAN BURNER
heck pilot and main burners at least every 12 months for
proper flame characteristics.
The proper flame should envelop approximately 10 mm (3/8
inch) of tip of thermocouple.
Figure 11
If the pilot flame is too small, then the pilot burner must be
cleaned. The position of the igniter electrode should also
be checked to assure that electrode is approximately 3mm
(1/8”) from pilot, see figure 11.
The main burner should exhibit the following characteristics:
- Provide complete combustion of gas.
- ause rapid ignition and carryover of flame across burners.
- Operate quickly during ignition, burning, and extinction.
Figure 12
If the main burners fail to exhibit above characteristics they
must be cleaned, either by blowing them off with compressed
air or by washing them in soap and water and rinsing.
If it proves necessary to wash the main burner assembly
the following procedure should be used:
1- Turn off the gas supply to the water heater.
2- Disconnect pilot gas tube at the gas valve and unscrew
the gas manifold assembly union nut, where the gas
manifold inlet pipe connects to the gas valve and remove
the gas assembly.
3- Wash in soap and water and then rinse.
4- Reassemble – heck for gas leaks after reassembly
and correct as required.
5- Refer to Lighting Procedure to relight the heater.
VENTING
The vent piping and finned heat exchanger should be checked
at least once a year for dust and carbon deposits, and
cleaned as necessary.
PRESSURE RELIEF V LVE
At least once a year the pressure relief valve should be
checked to insure that if it is in operating condition. Before
testing the relief valve take necessary precautions to prevent
water damage. Lift the lever on the valve several times until
the valve seats properly and operates freely. Do not check
the relief valve when hot water is being drawn and the main
burner is on. Water exiting the valve under these conditions
would be hot.
If the pressure relief valve on the appliance discharges this
is an indication of water pressure above the pressure rating
of the relief valve. If the pressure relief valve continually
discharges on a periodic basis contact the water supplier or
local plumbing inspector on how to correct the situation. Do
not plug the pressure relief valve.
PERIODIC REMOV L OF LIME DEPOSITS
After 12 to 24 months of service, depending on frequency
of use and water harness, the heater should be checked for
accumulation of calcium carbonate (lime) and delimed, if
necessary. Thereafter a regular schedule, based on initial
inspection findings, should be set up to delime the heater.

11
BOSCH INST NT NEOUS W TER HE TERS PPROVED
FOR SP CE H E TING UNDE R CL SS IV
When using the Bosch Models W 400-K for water heating and space heating the following requirements
shall apply :
All space heating equipment, piping and components connected to the heater shall be suitable for use
with potable water.
Toxic chemicals such as boiler treatment compounds, antifreeze etc, shall not be introduced into potable
water used for space heating.
When used for potable water this unit may not be connected to any heating system or components
previously used solely for space heating.
A temperature mixing valve must be installed where space heating temperature requirements are higher
than normal domestic supply temperatures to reduce scald hazard potential. Particular care must be
taken to select the correct type of thermal mixing valve to satisfy the installed application requirements,
i.e. If full anti-scald protection is specified then only that type of valve must be selected that is supported
by the manufacturer’s claim. Below is a typical schematic which should be used as a guide only.
Always obey the installation instructions supplied by the mixing valve supplier.
Cold Water Supply to
tempering regulator
Temperature Mixing
Valve Regulator
check
valve
Feed to Space
Heating Equipment
130°F Hot
Water Service
Supply to
Bosch Heaters
Return from Bosch
Heaters and
Space Heating
HOT W TER
STOR GE
T NK
Note: These schematics and explanatory text should not be
used for design purposes, but only as a general guide. Actual
system design and installation must be by qualified people.
SEPARATE PUMPS REQUIRED
FOR HEATER AND IR ULATION SYSTEM
Installations must conform to SA B214 hydronic standard
and local code requirements.

12

13
Nº Description
W325 K..P..T1 W 400 K…P…T2
1Front shell 8705401525
2 over
4Drau
g
ht diverter 8705505307 8705505354
5 Heat exchan
g
er 8705406132 8705406235
6 onnectin
g
p
i
p
e hot
7 old water
p
i
p
e
8 Washer 1/2"
9Tem
p
erature limit
10 Main burner LPG 8708120469 8708120296
10 Main burner NG 8708120471 8708120298
11 Pilot burner ( 75 )
11a Filter
12 S
p
arkin
g
p
lu
g
13 Pilot in
j
ector ( 5 ) NG
13 Pilot orifice (49) LPG
14 Pilot
g
as
p
i
p
e
15 Thermocou
p
le
16 Washer 1"
17 Throttle disc ( 7.0 ) LPG 8700100174
18 Gas valve NG 8707001890 8707011110
18 Gas valve LPG 8707001897 8707001942
19 Gas su
pp
l
y
p
i
p
e
20 Ma
g
netic unit
21 Washer
22 Gas filter
23 Termo connection
24 Water valve 8707002393 8707002478
25 Sealin
g
screw 8703406204 8703406214
26 Dia
p
hra
g
m 8700503050 8700503043
27 Slow-i
g
nition valve 8708503062 8708503060
28 Settin
g
screw 8703404092 8703404098
29 O-rin
g
30 Valve
31 Venturi (12) 8708205235
31 Venturi (16) 8708205248
32 Water strainer
33 water elbow fitin
g
Part Number for Models
8700507059
8700705472
8700705431
8700705294
8710103045
8707206017
8708105337
8700507055
8708107002
8703304011
8747201094
8700103144
8708200005
8748200173
8710707166
8747202083
8710103060
8700705464
8747202078
8708500230
8700205050
8700507051

ASTRAVAN DISTRIBUTORS, LTD.
123 harles Street
North Vancouver, B . V7H 1S1
Phone ( anada): [phone]
Phone (USA): [phone]
Site Internet: www.astravan.com

6 720 601 783 CA (03.11) AL
Chauffe-eau à gaz instantané
Modèles
W 325 K…T1
W 400 K…T2
Installation
Fonctionnement
Entretien
Le chauffe-eau instantané BOSCH est la réponse pour
haute éfficacité dans un espace restreint en satisfaisant
tout vos besoin d’eau chaude. Tous les chauffes- eaux
instantanés Bosch chauffent seulement la uantité d’eau
sur demande sans dépenser de l’énergie pour maintenir la
température élevé de l’eau dans le réservoir.
POUR VOTRE SECURITE
Ne pas placer ou utiliser de la gasoline ou tout autres
li uide et vapeur inflammable a proximité de ce brûleur
ou d’ autres appareils.
A noter : En cas de problème contacter votre vendeur ou l’ouvrier d’installation.
POUR VOTRE SECURITE
Si vous sentez un gaz odorant:
1. Ouvrir les fenêtres
2. Ne toucher pas à aucun contact électri ue
3. Eteindre toute flamme
3. Appeler immédiatement votre fournisseur de gaz
ASTRAVAN DISTRIBUTORS, LTD.
123 Charles Street
North Vancouver, B.C. V7H 1S1
Téléphone (Canada): [phone]
Téléphone (USA): [phone]
Site Internet : www.astravan.com

2
Dimensions
Figure 1
Pression maximum hydrostati ue de l’eau - 0.97 MPa ( 150 lb / po ca.)
Pression maximum d’opération recommander - 0.69 MPa (100 lb / po ca)
Pression minimum d’opération - 0.05 MPa (7.3 lb/po ca) au taux de débit minimum.
* La console de mur est re uis seulement pour le WR 325 K… uand il est installé dans une construction combustible.
Le WR 400K…T2 peut être installé directement à une construction combustible.
** Les évaluations de haute altitude dans cette liste sont les évaluations de l’évaluations de l’Association Canadien de gaz pour haute
altitude et sont utilisable seulement au Canada. Au Etats- Unis, le National Fuel Gaz Code, ANSI Z223.1-1984 recommandé pour
une installation de plus de 2,000 pieds au- dessus du niveau de la mer, ue la consommation soit réduite de 4% pour cha ue 1,000
pieds au- dessus du niveau de la mer. Voir page 8.
Dimension en milimètre (pouces)
Dimension, mm Qte
normale 29.30kW (100,000Btu/hr) 1.25 diam. 14
(0 - 2,000 Pieds) 27.83 kW (95,000Btu/hr)
Propane 0.79 diam. 14
haute** 26.37kW (90,000Btu/hr) 1.25 diam. 14
(2,000 - 4,500 Pieds) 25.05 kW (85,000Btu/hr)
Propane 0.79 diam. 14
normale 34.28 kW 1.25 diam. 16
(0 - 2,000 Pieds) (117,000Btu/hr)
Propane 0.82 diam. 16
haute** 30.85 kW 1.25 diam. 16
(2,000 - 4,500 Pieds) ( 105,000Btu/hr)
Propane 0.82 diam. 16
W400 Naturel
W400 Naturel
Orifices du brûleur principal
Modèle Type de gaz Altitude Consommation
W325
W325
Naturel
Naturel
Modèle A B C D E F G H
400 755 250 155 85 130 410 320
17 1/4" 29 3/4" 9 3/4" 6" 3 1/4" 5" 16 1/8" 12 5/8"
440 770 250 155 85 130 410 320
17 1/4" 30 1/4" 9 3/4" 6" 3 1/4" 5" 16 1/8" 12 5/8"
W400
W325

3
AVERTISSEMENT AU LECTEUR
Les caractéristi ues des chauffe- eau à gaz instantanés de
modèles W325 K et W400 K sont conformes au normes
CAN 1-4.3 et ANSI Z21-10 (dernière édition). De plus, les
modèles W325 K et W400 K répondent aux normes CAN
1-2.17 pour les applications à haute altitude, soit de 2000
à 4500 pieds au- dessus du niveau de la mer.
Le présent manuel contient les instructions d’installation de
fonctionnement et d’entretien de l’appareil. Avant de
procéder à l’installation du chauffe- eau à gaz instantané
BOSCH, il est recommandé de lire attentivement les
instructions se rapportant à l’installation et au fonctionnement
de l’appareil.
Le chauffe- eau à gaz instantané BOSCH est conçu de
sorte à pouvoir être adapté au propane ou au gaz naturel.
On doit toutefois S’ASSURER ue le combustible utilisé
pour alimenter le chauffe- eau est celui ui est spécifié sur
la pla ue signaléti ue du chauffe- eau.
En plus des instructions d’installation prévues ci- haut, les
chauffe- eau doivent être installés conformément au code
d’installation CAN/CGA- B149 (au Canada) ou à la dernière
édition du National Fuel Gas Code Z223.1 (aux États- Unis),
et/ou tout autre code d’installation local. Ces normes doivent
être respectées dans tous les cas.
INSTRUCTION D’INSTALLATION
A noter: Avoir la bonne plomberie, ventilation, connections
de gaz et une bonne provision d’air de combustion sont
re uis pour une opération efficace et sans ris ue. En plus il
est très important ue l’installateur soit bien ualifié dans le
métier d’installation et d’entretien de chauffe-eau à gaz.
EMPLACEMENT
Avant l’installation du chauffe- eau à gaz instantané BOSCH,
il faut prendre en considération l’endroit pour l’emplacement.
L’emplacement doit être proche d’une cheminée ou un évent
à gaz si possible et ue l’endroit offre une bonne provision
d’air et centré avec le système de tuyautage. Le chauffe-
eau W325K ne peut pas être installé dans un endroit ui
ne sera pas endommagé en cas de fuite du chauffe- eau ou
d’un de ces raccords.
A noter : Quand tels endroits sont pas évitable on
recommande u’un bassin d’égouttoir soit installé sous le
chauffe- eau avec un drainage adé uat. Le bassin d’égouttoir
ne doit pas empêcher la circulation d’air de combustion.
REQUISITION D’AIR
Pour une opération en sûreté, il faut avoir une uantité
suffisante d’air de combustion, ventilation et une dilution
des émanations. Si la uantité d’air est insuffisante, la flamme
du brûler sera de couleur jaunâtre et produira du sédiment
de carbonne ou de la suie à l’echangeur de chaleur. Dans
les espaces libres, dans les bâtiments de construction normal,
en général il y a assez d’infiltration pour la provision d’air de
combustion, ventilation et dilution des émanations.
Toutefois, dans un espace restreint, il faut faire deux
ouvertures permanentes pour la provision d’air de
combustion et ventilation pour l’appareil. Cha ue ouverture
doit avoir une superficie libre d’un pouce carré par 1000
BTU/Heure * du grand total de consommation de tous les
appareils dans l’espace restreint. Une ouverture sera à 12
pouces au dessus du sol et une autre á autre à 12 pouces
en-dessous du plafond.

4
Soit un espace ou restreint dans un bâtiment de
construction étroite avec une infiltration insuffisante, l’air
doit être tiré de l’extérieure ou d’espaces ui communi ue
avec le plein air. Les deux ouvertures mentionnées ci-dessus
doivent être pourvu comme suit :
. Quand la communication est directement avec le plein
air ou par les évents verticaux, cha ue ouverture doit
avoir une superficie libre pas moins u’un pouce carré
par 4000 BTU/heure du grand total de consommation
de tous les appareils dans l’espace.
. Quand la communication est avec le plein air par les
évents horizontaux, cha ue ouverture doit avoir une
superficie libre pas moins u’un pouce carré par 2000
BTU/heure du grand total de consommation de tous les
appareils dans l’espace.
Pour les exigences détaillées voir :
- Au Canada, CAN 1-B 149 Installation Codes (codes
d’installation)
- Dans les Etats- Unis, ANSI Z 223.1-1984 National Fuel
GAS Code.
AVERTISSEMENT
Matériaux combustibles, l’essence, récipient sous pression
ou n’importe uelles articles ui sont facilement combustibles
ne doivent pas jamais être placés sur ou près d’un appareil
de chauffage. L’endroit ou l’appareil est situé ne doit pas
contenir aucun matériaux combustibles , de l’essence, ou
d’autre vapeurs et li uides combustibles.
Ne pas obstruer la circulation de l’air combustible et
ventilation pour le appareil.
DEGAGEMENT
Le W 325 et le W 400 sont de conceptions certifié pour
l’installation sur un mur de construction combustible (pour
le W 325, la console de mur fourni avec l’appareil doit être
utilisé pour le montage sur une construction combustible)
et pour l’installation dans une alcôve ou un placard avec un
espace libre minimum à la construction combustible de 0mm
de l’arrière, 102mm (4 pouces) des côtées, 305mm (12
pouces) du haut et du bas et 102mm (4 pouces) du devant.
Un minimum de 305mm (12 pouces) doit être établi comme
espace pour l’entretien et service aux pièces de rechange.
Le dégagement pour l’éventail est selon le classement de
dégagement pour le matériel de l’éventail utiliser, c’est á
dire le type B-1 éventail est approuvez pour un espace de 1
pouce, le B-2 éventail pour 2 pouces, etc…
MONTAGE
Le W 325K et le W 400 K sont de conceptions certifiés
pour l’installation sur un mur. La console de mur, voir figure
1, est fourni avec le W 325K et doit être utilisé pour le
montage d’un appareil de chauffage sur un mur combustible.
Les appareils de chauffage ne peuvent pas être installer
directement sur un mur couvert de tapis. L’appareil de
chauffage ou la console de mur doit être monté sur le mur
avec une pla ue d’encrage.
AVERTISSEMENT
L’omission de la console de mur avec le W 325 K pour le
montage sur un mur combustible peut rendre les conditions
dangereuse avec le possibilité d’incendie. En plus, l’omission
de la console de mur pour le montage de W 325K.. sur une
construction combustible sera une infraction contre la
certification de l’appareil par l’ A.G.A et C.G.A..
Note : Si le mur est construit avec des montants couvert de
panneaux en enduit, on recommande ue les planches de
support soit 1x4’s, ou ½’’(minimum) contre-pla ué support
attacher aux montants pour le montage de l’appareil de
chauffage dans le cas de W 325 K.. doit être attaché aux
planches de support. Voir figure 2.
L’expansion et contraction de la tuyauterie, du au
changement de température de l’eau dans les tuyaux,
transmet le mouvement à l’appareil de chauffage, le uel, si
il est monté à un endroit pas solide comme les panneaux en
enduit, la monture peut être fragile et tomber.
Figure 2

5
L’EGOUTTOIR
Si l’appareil de chauffage est monté au-dessus du sol de la
construction combustible, l’égouttoir (fourni avec l’appareil,
détachée) doit être assemblé au bas du couvercle devant
l’appareil pendant l’installation.
L’égouttoir doit être attaché au couvercle du devant avec
les écroues fournient comme montré à la figure 3.
L’omission de l’usage de l’égouttoir uand l’appareil est
installé au-dessus du sol de construction combustibles peut
rendre les conditions dangereuse avec la possibilité
d’incendie et une infraction contre la certification de
l’appareil de A.G.A. et C.G.A..
Figure 3
VENTILATION
Les chauffes- eaux instantané Bosch sont construit avec
un directeur du tirage d’air et sont conçuent pour l’usage à
l’intérieure seulement. Le directeur du tirage d’air doit être
raccordé á un évent de la même grandeur ou plus grand,
propre de tout débris, référer à :
- Au Canada, CAN 1-B149 Installation Code pour les
exigences détaillées.
- Dans les Etats- Unis, ANSI Z 223.1- 1984 National Fuel
Gas Code pour les exigences détaillées.
5” X 6” adapteur est
utilisé pour haute
altitude Modèle W 400
seulement.
En haute altitude l’adaptateur doit être installé comme
montré à la figure 4, sans modification, avant le montage
du conduit de six pouces à l’appareil.
L’adaptateur doit être attacher sécurement au directeur du
tirage d’air avec un minimum de deux vises.
Aussi, au Canada le régulateur de pression du gaz fournie
avec le chauffe-eau est réglé à l’avance en usine pour livrer
la bonne pression de gaz au chauffe-eau pour un fonction-
nement en haute altitude, voir la section REGULATION DE
PRESSION dans ce manuel.
AVERTISSEMENT
L’omission d’agrandir la grandeur du conduit sur le W400
de six pouces et/ou s’assurer ue la pression du collecteur
est mise à la valeur indi uée sur l’éti uette d’évaluation
pour les applications à haute altitude de 2.000 à 4.500
pieds au dessus du niveau de la mer peut causer une
mauvaise ventilation, l’asphyxie et annuler la certification
de C.G.A..
LES RACCORDS D’EAU
Les séries W chauffes- eaux instantanés sont fournient avec
deux S- codes raccords/adaptateurs d’eau, les uelles doi-
vent être connectés aux connections d’entrée et de sortie
de l’eau sur le clapet d’eau, voir figure 1 et figure 5 ci-
dessous.
CLAPET D’EAU ET S.COUDES VUE DE HAUT
Figure 5
La raison pour les S-coude raccords/adaptateurs d’eau est
de procurer des connections d’eau filetés en accordance
avec les normes de l’Améri ue du Nord, ANSI standard taper
Pipe Thread (1/2’’ NPT).
L’alimentation de l’eau froide doit être raccordé au S-coude
attaché á l’entrée du clapet d’eau et la connection á l’eau
chaude doit être raccordé au S-coude attaché à la sortie
du clapet d’eau.
A noter: Un robinet d’arrêt doit être placé dans le tuyau
d’alimentation d’eau froide du chauffe-eau pour y faciliter
l’entretien.
Figure 4

6
SOUPAPE DE SURETE
La soupape de sûreté fourni doit être installé au moment de
l’installation du chauffe-eau. Aucun autre robinet doit être
installé entre la soupape de sûreté et le chauffe-eau. Un
tuyau d’écoulement doit être raccordé à la soupape de sûreté
pour le drainage soit dirigé en lieu sûr. N’installer pas aucune
réduction mâle- femelle ou autres restrictions dans le tuyau
d’écoulement. Le tuyau d’écoulement doit être installé de
façon à faciliter un drainage complet pour la soupape de
sûreté et la tuyauterie. Voir figure 6.
Figure 6
RACCORDS DE GAZ
Avant de raccorder l’alimentation de gaz au chauffe- eau,
vérifier l’éti uette de modèle/évaluation du chauffe- eau
pour s’assurer ue le gaz d’alimentation est le même
u’indi uer sur l’éti uette de modèle/évaluation.
Le W 400K et le W 325K chauffe-eau au gaz instantané
sont munient d’un régulateur de pression à gaz ui doit être
installé au chauffe-eau avant le raccordement du tuyau
d’alimentation du gaz, voir figure 7. L’omission d’installer le
régulateur dans l’ordre montré à la figure 7 sera une infraction
contre la certification de l’appareil de l’ A.G.A. et C.G.A..
Les chauffes-eaux BOSCH sont expédier de l’usine avec
le régulateur de pression à gaz déjà ajusté tel u’indi ué
sur la pla ue d’évaluation :
- Au Canada, pour le fonctionnement à haute altitude.
- Au Etats- Unis, pour le fonctionnement à altitude
normale, sauf si indi ué comme un appareil de haute
altitude.
Vérifier pour être certain ue le gaz indi ué sur la pla ue
d’évaluation est le même ue le gaz indi ué sur le régulateur
de pression. VOIR REGLEMENT DE PRESSION dans ce
manuel pour l’information concernant le réglage de pression
à gaz.
A noter: Avant de raccorder le tuyau d’alimentation de gaz
vérifier ue l’intérieure du tuyau est propre. Pour se
débarrasser de la saleté et de toutes corps étrangers dans
le tuyau d’alimentation de gaz, un mamelon purgeur doit
être installé dans la tuyauterie. Le mamelon purgeur doit
être accessible et sans danger de gel. L ‘installation doit
être en accordante avec les recommandations du fournisseur
de gaz.
Le composé de l’encolleuse (le composé du filetage) doit
être appli ué avec modération et seulement au filetage mâle.
N’appli uer pas le composé au deux premier filets. Le
composé du filetage doit résister au gaz li uéfié.
Avant de mettre le chauffe-eau en opération vérifiez pour
toute fuite de gaz. Une solution d’eau et savon ou autre
matériel acceptable pour ce travail être utilisé pour localiser
les fuites de gaz. Des allumettes, bougies, allume-cigarette
ou d’autre source d’allumage sont défendent pour ce travail.
AVERTISSEMENT
Le chauffe-eau et ces robinets de fermeture doivent être
détachés du système de tuyauterie d’alimentation de gaz
pendant la vérification de ce système au- dessus de 3.45
kPa (1/2 Lb/po.ca.)
Le chauffe-eau doit être isolé du système de tuyauterie
d’alimentation de gaz par son robinet de fermeture pendant
la vérification de pression du système à une pression égal
ou moins ue 3.45 kPa (1/2 Lb/po.ca.)
Le chauffe-eau, y compris le régulateur de pression et le
robinet manuel fourni, ne doivent pas fonctionner à une
pression de gaz au-dessus de 3.45 kPa (1/2 Lb/po.ca.).
Si il y a une surpression ui se développe soit par une
mauvaise vérification de la pression de gaz ou un mauvais
fonctionnement du système d’alimentation d’urgence, le
robinet de gaz et le régulateur doivent vérifier pour un
fonctionnement en toute sécurité. Etre certain ue les clapets
d’échappement à l’extérieure sont protégés contre toute
obstruction. Ils font partie du système d’alimentation de gaz
et non du chauffe-eau. L’obstruction du clapet
d’échappement peut se produire pendant les tempêtes de
neige.
Figure 7
ROBINET DE PRESSION
REGULATEUR DE
PRESSION