Bosch WR430-3K Owner's manual

6 720 606 181 CA (03.11) AL
Model
WR430-3K
• 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;
no energy is lost maintaining a large volume of water at
elevated temperatures as in tank-type storage water heaters.
Suita le for heating pota le water only. Not approved for
space heating purposes.
POWER VENTED - ELE TRONI IGNITION
ASTRAVAN DISTRIBUTORS, LTD.
123 Charles Street
North Vancouver, B.C. V7H 1S1
Phone Canada: [phone]
Phone USA: [phone]
We Site: www astravan.com
Note: In case of problems please contact your salesman or installer
NOTI E TO INSTALLER: Please leave this
manual with the owner or affix adjacent to
appliance.
Instantaneous gas water heater
WARNING: If the information in this
manual is not followed exactly, a fire or
explosion may result causing property
damge, personal injury or death.
- Do not store or use gasoline or other
flammable vapors and liquids in the vicinity of
this or any other applicance
- WHAT TO DO IF YOU SMELL GAS
• 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, service agency or the gas
supplier.
READ INSTRU TIONS AREFULLY BEFORE INSTALLING

2
Water Connection 1/2” Thread fitting
H x W x D 29 3/4” x 18 1/4” x 8 3/4”
Vent 4” (Category III Gas Appliance)
Max. lineal vent pipe length 15’ (4.5m)
Gas Connection 1/2” NPT thread
Shower pressure 40 Psi
Min. Water Pressure 18 Psi (no fittings attached)
Max. Water Pressure 150 Psi
Shipping Weight 50.6 LB
Net Weight 44 LB
2.5 GPM at 90° rise (32°C) (9.5 l)
5.0 GPM at 45° rise(16°C) (19.5 l)
Min. Water Flow 1/2 gal/min
120V/60Hz 1.2 Amps
LP GAS Supply Pressure inlet. min. 11”W.C.*
LP GAS regulator outlet pressure 9.9”W.C.*
Natural Gas Pressure inlet min.: 7”W.C.*
Natural Gas Regulator Pressure 5.38 W.C.**
* Inlet gas pressure must not exceed this value
** For purposes of input adjustment
ELECTRICAL 3 ft. ( 0.9 m) power ca le supplied c/w CSA
3 prong plug.
UNPA KING THE BOS H WR430-3K HEATER
This heater is packed securely. The ox includes two water connection fittings, a control kno , a gas pressure regulator, a
pressure relief valve, an incandescent particle tray, two hooks for hanging the heater, this manual. Do not lose this manual
as there is a charge for replacement.
BOS H WR430-3K
Principle of Operation:
When a hot water faucet is opened, the flow of water through
the heater causes the gas valve to open. At the same time
a microswitch is activated which sends a spark to the pilot.
The flame sensor confirms that the pilot has een lighted
and allows urners to ignite. The pilot goes out. The power
exhaust system runs as long as the urners are on. The
heat exchanger coils a sor the heat generated y the
urners and transfer heat to the water. When the hot water
faucet is shut off, the gas valve automatically closes and
the urners turn off, followed immediately y the exhaust
system. Your hot water faucet is an ignition key to turn on
the water heater, giving you control over your hot water energy
use. Every time you turn off your hot water faucet, the energy
consumption for hot water returns to zero.
FEATURES
- Power Venting with safety shutoff
- Electronic Pilot Ignition
- On/Off switch to activate system
- High Quality Materials for Long Working Life.
- Copper heating coils for endless supply of hot water.
- Burner output proportional to hot water flow demand for
maximum energy efficiency.
- Safety flame sensor at pilot urner.
- Automatic over heating protection shut-off sensor.
- Stainless steel urners with sta ilized lue flame.
- Built-in corrosion resistant power venter.
- Compact space saver: mounts on a wall with two hooks.
- Easily remova le one-piece cover.
- Easy one person installation.
- Adjusta le water flow restrictor ensure that water flow
demand will not exceed the heating capacity of the heater.
NAT. GAS PROPANE
max. 130 000 Btu/hr 125 000 Btu/hr
Gas Input min. 28 000 Btu/hr 28 000 Btu/hr

3
DIMENSIONS
Figure 1
Maximum Hydrostatic water pressure - 1.03 MPa (150 p.s.i.)
Maximum recommended working pressure - 0.69 MPa (100 p.s.i.)
Minimum working pressure - 0.09 MPa (13 p.s.i.) no piping attached
Reccomended pressure for showers and domestic, 0.27 MPa (40 p.s.i.)
• The high altitude ratings listed are Canadian Gas Association high altitude ratings and are valid only in Canada. In the U.S., the
National Fuel Gas Code, ANSI Z223.1-1988, recommends for high altitude installations a ove 2,000 feet, that the input rate e
reduced 4% for each 1,000 feet a ove sea level. - See page 14.
D084_089
EXTERIOR
TERMINATION
Model Type of Gas Altitude Input
Size, mm Qt.
1.20 diam. 18
WR430-3.K.. 0.79 diam. 18
1.20 diam. 18
0.79 diam. 18
Main Burner Orifices
natural gas
propane
0 - 2 000 ft 130 000 Btu/hr (38 kW)
2 - 4 500 ft 116 000 Btu/hr (34 kW)
0 - 2 000 ft 125 000 Btu/hr (36 kW)
2 - 4 500 ft 112 000 Btu/hr (33 kW)

4
FORWARD
The design of the WR430-3K complies with CAN 1-4.3
and ANSI Z21.10 (latest edition) as an instantaneous gas
water heater. In addition, the WR400-3K also complies with
CAN 1-2.17 for use at high altitudes, 2,000 - 4,500 ft. a ove
sea level.
Installation, operation and maintenance instructions are
provided in this manual. Installation and operation
instructions should e thoroughly reviewed efore
proceeding with installation of the BOSCH instantaneous
gas water heater.
Note: Proper plum ing, venting, gas connections and an
adequate supply of com ustion air are required for
safe and relia le operation. A ility equivalent to that
of a licensed tradesman in the field involved is
required for installation and/or service of these water
heaters.
LO ATION
Before installing the BOSCH instantaneous gas water
heater, consideration must e given to proper location. The
location should e as close to outside vent termination as
practica le, in an area with an adequate air supply and as
centralized with the piping system as possi le. The heater
should not e located in an area where it will e su ject to
freezing. The heater should e 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. See venting page 5.
Note: When such locations cannot e avoided, it is
recommended that a suita le drain pan, adequately
drained, e installed under the water heater. The pan
must not restrict com ustion air flow.
ELE TRI AL
A grounded switched plug recepta le must e provided
immediately elow the left hand corner of heater to accept
and provide power to supplied 3 ft. (0.9m) appliance ca le
and plug.
INSTALLATION INSTRU TIONS
The Bosch WR430-3K is a high efficiency fin tu e heater and should not e installed and operated during construction or
uilding renovations if location is exposed to a ove normal dust levels. This can cause dust uild up in the finned heat
exchanger and result in damage to heater and e a hazard to health.
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 instructions, the water heater shall e
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 codes. These
shall e carefully followed in all cases.
AIR REQUIREMENTS
For safe operation, sufficient air for com ustion, ventilation
and dilution of flue gases must e availa le. An insufficient
supply of air will result in a yellow luminous urner flame,
causing car oning or sooting of the heat exchanger.
In order to prevent corrosion, make sure that the com ustion
air is kept free of aggressive su stances. Su stances that
especially contri ute to corrosion are halogenated
hydrocar ons (e.g., chlorine and fluorine) which are
contaned in solvents, paint, adhesives, propellant gases,
various household cleaners, etc. Take precautionary
measures as necessary.
In unconfined spaces, in uildings of normal construction,
infiltration normally is adequate to provide air for com ustion,
ventilation and dilution of flue gases. However, a confined
space must e provided with two permanent openings to
provide com ustion and ventilation air to the appliance. Each
opening shall have a free area of one square inch per 1,000
Btu/Hr* of total input rating of all the appliances in the
enclosure. One opening shall e within 12 inches of the
top and one within 12 inches of the ottom of the enclosure.
* Special Note
When the WR430-3K is installed in a confined space of
minimum size the openings descri ed a ove must e
increased in to a size of 1-1/2 square inches per 1,000
BTU/Hr. In other words, when installed in a minimum sized
confined space the two openings that are to e made in
the enclosure within 12 inches of the top and 12 inches of
the ottom must each have a minimum free area of, (1-1½”
- 2" x (130) = 195 square inches.

5
Expansion and contraction of piping due to changing water
temperature in the pipes imparts movement to the heater
which, if mounted directly to a rittle, fria le oard, such as
plaster oard, can cause failure of mounting.
For either a confined or unconfined space in a uilding of
tight construction with inadequate infiltration, air must e
drawn from the outdoors or from spaces that freely
communicate with the outdoors. Two permanent openings
located as indicated are to e provided as follows:
1. When communicating with outdoors directly or by
means of vertical ducts, each opening shall have a
free area of not less than one square inch per 4,000
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 2,000 BTU/Hr. of
total input of all appliances in the space.
For detailed requirements see:
• in Canada, CAN/CGA-B149 Installation Codes
• in U.S.A., ANSIZ223.1-latest edition, National Fuel Gas
Code.
WARNING!
1. Flamma le materials, gasoline, pressurized containers,
or any other items or articles that are potentially fire
hazards must never e placed on or adjacent to the
heater. The appliance area must e kept free of all
com usti le materials, gasoline and other flamma le
vapors and liquids.
2. Do not o struct the flow of com ustion and ventilation
air to the appliance.
LEARAN E
The WR430-3K is design certified for installation on a
com usti le wall and for installation in an alcove or closet
with minimum clearances to com usti le construction of 0
mm from ack, 102 mm (4 inches) from sides, 305 mm (12
inches) from top and ottom, and 102 mm (4 inches) from
front. A minimum of 305 mm (12 inches) shall e allowed
for maintenance of servicea le parts. Clearance from vent
is dependent upon the clearance rating of the venting
material used; see venting page 6.
THIS APPLIANCE MUST BE INSTALLED IN ACCORDANCE WITH THE NATIONAL FUEL GAS CODE ANSI Z223.1-
latest edition in U.S.A. or CAN/CGA-B149 INSTALLATION CODES IN CANADA. LOCAL CODES AND/OR THE
REQUIREMENTS OF THE AUTHORITY HAVING JURISDICTION MUST BE FOLLOWED.
MOUNTING
The WR430-3K is design certified for mounting to a wall.
The heater must not e installed on a carpeted wall. The
heater must e mounted to the wall using appropriate
anchoring materials.
Note: If wall is a stud wall sheathed with plaster oard it is
recommended that support oard(s), either 1 x 4's
or 1/2” (minimum) plywood first e attached across
a pair of studs and then the heaters should e
attached to the support oards. See Figure 2.
Figure 2
Fig. 2 - Mounting the Heater
WALL STUDS
1” X 4”
SPACE BOARD
SUPPORT BOARD

6
Bosch POWER VENTING SYSTEM
INTRODU TION
Bosch power venting models are designed to overcome difficult venting pro lems which cannot e performed
with atmospheric venting: to meet your hot water demand load very efficiently, with an environmentally friendly
appliance which conserves energy and significantly reduces com ustion emissions to atmosphere.
GENERAL INFORMATION
This Power Vent System must e installed y a *qualified installer in accordance with all applica le local gas
and electrical codes and in the a sence of:
• With the current CAN1/CGA B149 installation code for gas urning appliances and the Canadian Electrical
code C22.1-M90 part 1 (for anada).
• With the National Fuel Code and the ANSI Z223.1-LATEST and National Electrical Code ANSI/NFPA No
70-LATEST electrical code (for USA).
The Bosch warranty will e voided y, and Bosch disclaims any responsi ility for the following actions:
• Use of any unapproved venting component part not manufactured or approved y Bosch in com ination
with the Bosch WR430-3K unit.
• The Bosch WR430-3K must not e modified in any way when installing the Power Vent System. All
systems must e installed as per Bosch Installation Guide.
• Installation other than instructed in this manual.
AUTION:
Bosch Power Vent System must be installed by a qualified agency in accordance with these instructions.
If improperly installed a hazardous condition such as an explosion or arbon Monoxide poisoning
could result. Bosch will not be responsible for any and all improperly installed appliances.
*QUALIFIED INSTALLING AGEN Y: Any individual, firm, corporation or company which either in person or
through a representative is engaged in and is responsi le for the installation and operation of gas appliances and
draft control devices, who is experienced in such work, familiar with all precautions required, and has complied
with all the requirements of the authority having jurisdiction.
GENERAL VENTING INFORMATION
SIZING & DISTAN ES:
Plan the vent system so that code clearances and manufacturer’s distances are maintained from com usti le
materials, plum ing and wiring.
This unit may e directly connected to approved vent termination with a 90° el ow or located with a maximum
lineal length of 15 ft. (4.6m) including two 90° el ows from termination. All vent pipe and fittings must only e
4” (10.2cm) in diameter.

7
Bosch POWER VENTING SYSTEM
GENERAL VENTING INFORMATION - continued
APPROVED VENTING MATERIALS:
Single wall:
As gauge listed in the current CAN1/CGA B149 installation code for gas urning appliances (for Canada),
National Fuel Code ANSI Z223.1-LATEST (for USA).
Note: annot be used in concealed locations.
B-Vent materials:
Straight lengths only (no el ow) may e used under following conditions
(i) Unsealed 5” B-vent may e used as a chase for sealed 4” single wall through concealed or unheated
areas.
learances to combustible materials for walls and partitions:
• 1” (25mm) for B-Vent.
• 3” (76mm) for single wall and uninsulated PVS-1 vent piping.
A wall thim le must e installed for internal wall applications.
All runs through unheated space or exposed to outside temperatures must e insulated to prevent condensation.
All portions of the vent system under positive pressure during operation (on the outlet side of the WR430-3K)
shall e sealed with high temperature silicone and high temperature aluminum duct tape and installed so as to
prevent leakage of flue or vent gases into uilding.
GENERAL ODE REQUIREMENTS
Before commencing an installation always consult with local gas and electrical codes and authorities, in the
a sence must e installed:
• With the current CAN1/CGA B149 installation code for gas urning appliances and the Canadian Electrical
code C22.1-M90 part 1 (for anada).
• With the National Fuel Code and the ANSI Z223.1-LATEST and National Electrical Code ANSI/NFPA No 70-
LATEST electrical code (for USA).

8
Bosch POWER VENTING SYSTEM
VENT TERMINAL INSTALLATION:
Before installing Bosch WR430-3K determine the location of vent system termination which may e immediately
connected with a 90° el ow or with a maximum lineal length of 15 feet including two 90° el ows. (See Fig. 1)
Note: In cold climate areas negative air pressure such as unbalanced heating and ventilating systems can
cause reverse air flows in gas vent and chimney systems. Under extreme cold conditions this can cause
freezing and damage Bosch heat exchanger during prolonged period of times when they are not in use,
such as night time hours. Vent termination with back draft flapper is supplied in order to minimize outside
air infiltration and risk of freezing equipment.
The approved terminal shall e so arranged for flue gases to e directed in a manner which will not jeopardize
people, overheat com usti le structures or enter into uildings, and that proper clearances are maintained (See
Fig. 2 )
a) The vent terminal of this Power Vent System shall not e less than 7 feet (213cm) a ove grade when
located in areas accessi le to pu lic walkways.
) A vent terminal shall terminate at least 3 feet (91cm) a ove and a minimum of 10 feet (305cm) horizontally
from any (mechanical) air inlet.
c) The vent terminal shall not e within 6 feet (183cm) radius from a gas meter or regulator, and horizontally
it must e a minimum of 3 feet (91cm) from the centre line of such regulator.
d) The vent terminal shall e a minimum of 6 feet (182cm) from any com ustion air inlet.
e) The vent terminal shall terminate from an opening window, at least 4 feet (122cm) elow or elow the
opening and 12 inches (30cm) horizontally. From a door 1 foot (30cm) a ove and 9 inches (23cm)
horizontally.
f) The vent terminal shall not e less than 3 feet (91cm) from an adjacent uilding.
g) The vent terminal shall not e less than 2 feet (61cm) a ove grade.
90° el
12 ft straight
(5.7m)
90° el
90° el
90° el
15 ft straight
(4.6m)
3 ft straight
(0.3m)
MAXIMUM LENGTH OF ALL PIPE LENGTHS
MUST NOT EX EED 15 FT (4.6M)

9
Bosch POWER VENTING SYSTEM
VENT INSTALLATION
1. Choose approved terminal location
2. Cut vent terminal opening through outside wall - Refer to installation instructions supplied with termination.
3. Install vent terminal y fastening from outside with 4 screws and caulking around flange edge. Check that
optional flapper moves freely if applica le.
4. Install 4” venting materials and secure all joints with a minimum of four screws for each joint. Please note that
wherever possi le use continual lengths of pipe to reduce the num er of joints.
5. Seal all positive vent pipe and el ow joints etween Bosch unit and vent terminal with high temperature
silicone and/or hi temperature aluminum tape following manufacturer’s instructions (i.e. always push silicone
ahead of nozzle)
ELE TRI AL WIRING:
1. The electrical contact ratings are as follows:
______ 1/10 HP at 120 VAC
______ 3 Amps (full load) at 120 VA
2. Provide switched plug receptacle to accommodate Bosch grounded plug.
3. Make certain the power source is adequate for the fan motor requirements.
Figure 2
REGULATOR VENT
72”
72”
36” 36”

10
Bosch POWER VENTING SYSTEM
VENT INSTALLATION (continued)
6. Support venting duct with plum er’s strap (supplied y installer). Solid piping need only e supported every
four feet. All horizontal pipe joints must e secured with a minimum of four screws per joint. (See Figure 3)
7. All runs through unheated spaces must e wrapped and insulated with a minimum of 1” insulation.
OPERATION AND HE KING THE DRAFT
A. Place Bosch appliance into operation. Follow lighting pilot and operating instructions on Bosch
cover.
1. Draw water continuously to activate appliance which will turn on gas urner.
2. CHECKING THE DRAFT. Operate the appliance with cover in place for a minimum of five minutes and
check for proper venting, and assure that the com ustion products are venting properly, y passing a
lighted match flame or smoke taper over the top edge of the Bosch cover and towards draft hood. If the
vent is drawing properly, the smoke or match flame will e drawn over the top edge of the Bosch cover
and into the draft hood or opening. (see drawing elow Checking The Draft)
NOTE: If smoke is not drawn in then the combustion products are
escaping from the relief opening into the room. Under these
conditions, the equipment shall not be operated until proper
adjustments or repairs are made to provide adequate draft.
3. Check draft spill safety switch y o structing outside vent terminal and y drawing water. Spill switch
should trip and shut off gas supply to Bosch unit. Remove outside o struction.
4. If spill switch trips allow 5 minutes to reset.
HE KING THE DRAFT
Figure 3
Vent support hangers (plum er's
strapping) should e 4 ft. apart on
horizontal runs.
All joints must e sealed with high temperature silicone
and high temperature aluminum vent pipe tape
RIGID PIPE
positive pressure
All clamped joints on the positive
side of the power venter are to
e sealed with high temperature
silicone.
Use 4 screws
per joint