Bosch WR 11 B Technical Document

Installation Manual and Operating Instructions
Gas Instantaneous Water Heater
WR 11/14/18 .B..
6720648592 (2014/05) ZA
Read installation manual prior to installation of this unit!
Read user manual before putting this unit in operation!
Observe the warnings in the manuals!
The installation room must fulfill the ventilation requirements!
Installation by an authorised person only!

6720648592 (2014/05)
2 | Table of contents
Table of contents
1 Key to symbols and safety instructions . . . . . . . . . . 3
1.1 Key to symbols . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Safety Instructions . . . . . . . . . . . . . . . . . . . . 3
2 Technical Characteristics and Dimensions . . . . . . . 5
2.1 Declaration of conformity with relevant
EEC regulations . . . . . . . . . . . . . . . . . . . . . . .5
2.2 Explanation of Model Code . . . . . . . . . . . . . . 5
2.3 Accessories (Included with Appliance) . . . . 5
2.4 Description of the heater . . . . . . . . . . . . . . . 5
2.5 Type overview . . . . . . . . . . . . . . . . . . . . . . . . 5
2.6 Special accessories . . . . . . . . . . . . . . . . . . . . 5
2.7 Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.8 Electrical diagram . . . . . . . . . . . . . . . . . . . . . 7
2.9 Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.10 Technical characteristics . . . . . . . . . . . . . . . 8
3 Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 Before starting up the heater . . . . . . . . . . . . 9
3.2 Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 Turning the heater on and o . . . . . . . . . . . . 9
3.4 Power adjustment . . . . . . . . . . . . . . . . . . . . 10
3.5 Temperature/ow adjustment . . . . . . . . . . 10
3.6 Purge the appliance . . . . . . . . . . . . . . . . . . 10
3.7 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 Regulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5 Installation (must be carried out only by
qualied technicians) . . . . . . . . . . . . . . . . . . . . . . . 11
5.1 Important information . . . . . . . . . . . . . . . . . 11
5.2 Selection of the place of installation . . . . . 11
5.3 Heater mounting . . . . . . . . . . . . . . . . . . . . . 12
5.4 Water connection . . . . . . . . . . . . . . . . . . . . 12
5.5 Gas connection . . . . . . . . . . . . . . . . . . . . . . 13
5.6 Inlet/exhaust pipe installation . . . . . . . . . . 13
5.7Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6 Adjustments (must be carried out only by
qualied technicians) . . . . . . . . . . . . . . . . . . . . . . . 13
6.1 Factory regulations . . . . . . . . . . . . . . . . . . . 13
6.2 Pressure adjustment . . . . . . . . . . . . . . . . . . 14
6.3 Conversion to a dierent type of gas . . . . . 15
7 Maintenance (must be carried out only by
qualied technicians) . . . . . . . . . . . . . . . . . . . . . . . .16
7.1 Periodic maintenance work . . . . . . . . . . . . 16
7.2 Startup after maintenance work . . . . . . . . 16
7.3 Flue gas safety device . . . . . . . . . . . . . . . . . 17
8 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
9 Environment / disposal . . . . . . . . . . . . . . . . . . . . . . . 19

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Key to symbols and safety instructions | 3
1 Key to symbols and safety instructions
1.1 Key to symbols
Warnings
The following keywords are dened and can be used in this
document:
•NOTICEindicates a situation that could result in damage to
property or equipment.
•CAUTIONindicates a situation thatcould result in minor to
medium injury.
•WARNINGindicates a situation thatcould result in severe
injury or death.
•DANGERindicates a situation that will result in severe
injury or death.
Important information
Additional symbols
1.2 Safety Instructions
If there is a smell of gas:
Close the gas valve.
Open windows.
Do not operate any electrical appliances or switches (on/
o).
Extinguish any naked ames.
Phone the gas company or an authorized technician from a
safe distance.
If there is a smell of burnt gases:
Disconnect the appliance.
Open doors and windows.
Inform an installation company.
Burn-back (re in burner tube or chamber)
In the event of a burn-back, where the ame burns back to
the injector, immediately turn o the gas supply at the
control valve on the panel.
After ensuring the ame isextinguished, wait for one
minute and re-light the appliance in the normal manner.
Should the appliance again burn back, close the control
valve and call a service technician.
Do not use the appliance again until the service technician
has declared that it is safe to do so.
Fitting, modications
The tting and modication of the installation of the
appliance must be carried out only by an authorized
technician.
The installation ofthe water heater mayonly be carried out
by a registered installer andthat such installations shall
comply with the requirements of SANS 10087-1.
The pipes carrying burnt gases must not be modied.
Do not close or reduce air circulation holes.
Maintenance
We reccomend to have the system regularly serviced in
order to ensure that it functions reliably and safely.
The installer is responsible for the safety and
environmental compatibility of the installation.
The appliance should be serviced annually.
Only original spareparts must be used.
Explosive and inammable materials
Inammable materials (paper, solvents, ink, etc.) should
not be stored near the appliance.
Combustion air and ambient air
To avoid corrosion, combustionair and ambient air should
be free of aggressive substances (for example halogenated
hydrocarbons containing chlorine and uoride
composites).
Warnings in this document are identied by
a warning triangle printed against a grey
background.
Keywords at the start of a warning indicate
the type and seriousness of the ensuing risk
if measures to prevent the risk are not taken.
This symbol indicates important information
where there is no risk to people or property.
Symbol Explanation
Step in an action sequence
Cross-reference to another part of the document
•List entry
– List entry (second level)
Table 1

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4 | Key to symbols and safety instructions
Important information for the user
This appliance may only be installed by a registered LP Gas
installer.
All registered installers are issued with a card carrying their
registration number.
Ask to be shown the card before allowing the installation
work to commence and make anote of the Installer QCC
number. Upon completion of the installation, the installer is
required to explain the operational details of the appliance
together with the safety instructions. You will be asked to
sign acceptance of the installation and be provided with a
completion certicate. You should only sign for acceptance
of the installation whenthe installationis completed to your
satisfaction.Note that your invoice is required in the event
that you wish make a guarantee claim.
Important information for the installer
This appliance may only be installed by a LP gas installer
registered with the Liqueed Petroleum Gas Association of
Southern Africa.
The appliance must be installed in accordance with the
requirements of SANS 10087-1 and any re department
regulations and/or local by lawsapplicable to the area. If in
doubt check with the relevant authority before undertaking
the installation.
Upon completion of the installation you are required to fully
explain and demonstrate to theuser the operational details
and safety practices applicable to the appliance and the
installation.
Client information
Inform the client about the function and operation of the
appliance.
Caution clients against performing modications or repairs
themselves.
Risk of damage dueto operator error
Operator errors can result in injury and damage to property.
Ensure that children never operate this appliance
unsupervised or play with it.
Ensure that only personnel who can operate this appliance
correctly have access to it.

6720648592 (2014/05)
Technical Characteristics and Dimensions | 5
2 Technical Characteristics and Dimensions
2.1 Declaration of conformity with relevant EEC
regulations
This appliance fullls European directive requirements 2009/
142/EC, 2006/95/EC, 2004/108/EC and corresponds to the
specications described in the corresponding EEC certicate
of proof.
2.2 Explanation of Model Code
[W] Gas Water Heater
[R] Proportional power adjustment
[11] Capacity (l/min)
[B] Electronic ignition powered by 1.5 V batteries
[23] Indicator number of natural gas H
[31] Indicator number of LPG
[S...] Country code
The code number indicates the gas group according to EN 437:
2.3 Accessories (Included with Appliance)
•Gas water heater,
•Attachment elements,
•Installation accessories,
•Two 1.5 V batteries type R
•Heater documentation.
2.4 Description of the heater
Operating convenience, as the heater is ready to operate by
simply pressing a switch.
•Heater for wall-mounting,
•Ignition by electronic devicetriggered when the water valve
opens,
•Great savings in comparisonwith conventional heaters,
due to the possibility of power adjustment and no
permanent pilot ame,
•Natural gas/LPG burner,
•Semi-permanent pilot burner which only functions during
the period between the opening of the water valve and the
ignition of the main burner,
•Heat exchanger in copperwithout tin/lead covering,
•Water valve in breglass-reinforced polyamide, 100%
recyclable,
•Automatic adjustment of the water ow by means of a
device which permits a constant ow to be maintained in
spite of variable pressure supplies,
•Gas ow adjustment proportional to the water ow to
maintain a constant high temperature.
•Safety devices:
– Ionisation probe to check for accidental extinction of
the burner ame,
– Flue gas safety device whichturns o the heater in case
of inadequate combusted gas evacuation conditions,
– Temperature limiter which prevents overheating of the
heat exchanger.
2.5 Type overview
The type plate is located at the bottom left of the appliance.
There you will nd details ofappliance output, model number,
approval data and the serial number.
2.6 Special accessories
•Conversion kit from natural gas to butane/propane.
Model WR 11/14/18 B...
Category II2H3+
Type Type B
Table 2
WR 11 B 23
31
S....
WR 14 B 23
31
S....
WR 18 B 23
31
S....
Table 3
Identication
Code
Wobbe Index (Ws)
(15 °C) Gas type
23 12,7-15,2 kWh/m3Natural Gas - Group H
31 20,2-21,3 kWh/m3LPG - Group B/P
Table 4

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6 | Technical Characteristics and Dimensions
2.7 Dimensions
Fig. 1
[1] Front cover
[2] Hole for xing to wall
[3] Temperature control
[4] Led indicator for battery charge level
[5] ON/OFF switch
[6] Led indicator for burner status
[7] Output control
[8] Gas connection
[9] Flue socket
[10] Draught diverter with ue gas monitor
[11] Heat exchanger
[12] Automatic gas valve
[13] Igniter unit
[14] Battery compartment
Dimensions (mm) A B C D E F G
H (Ø)
Natural
gas LPG
WR11B 310 580 228 112,5 463 60 25 1/2” 1/2”
WR14B 350 655 228 132,5 510 95 30 1/2” 1/2”
WR18B 425 655 334 132,5 540 65 30 1/2” 1/2”
Table 5 Dimensions

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Technical Characteristics and Dimensions | 7
2.8 Electrical diagram
Fig. 2 Electrical diagram
[1] Servo valve (normally open)
[2] Diaphragm valve
[3] Main valve (normally closed)
[4] Ionisation detector
[5] Igniter electrode
[6] Flue gas safety device
[7] Temperature limiter
[8] Igniter unit
[9] LED indicator for battery charge level
[10] LED indicator for burner status
[11] ON/OFF switch
[12] Batteries, 1.5V
[13] Microswitch
2.9 Function
This gas heater is equipped withautomatic electronic ignition
which simplies its operation.
To do so, just turn on the switch (Fig. 5).
After this procedure, automaticignition occurs whenever a hot
water tap is opened. First, the pilot burner is lit and
approximately four seconds afterwards the main burner. The
pilot burner ame is then extinguished after a short period of
time.
This is a way of saving a greatamount of energy as the pilot
burner only operates for the minimum necessary time to ignite
the main burner, in contrastto conventional systems which
operate permanently.
If this happens:
Close and open the hot watertap to repeat the ignition
process until all the air has been purged.
Air in the gas supply pipe when the heater is
started up may cause ignition to fail.

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8 | Technical Characteristics and Dimensions
2.10 Technical characteristics
Technical characteristics Symbol Units WR11 WR14 WR18
Power and ow
nPrewoplufesulanimoN Btu/h 65570 80595 104165
nimPrewoplufesumuminiM Btu/h 23905 23905 23905
Useful power (adjustment range) Btu/h 23905-
65570
23905 -
80595
23905 -
104165
nQwolflamrehtlanimoN Btu/h 74450 92210 117825
nimQwolflamrehtmuminiM Btu/h 27660 27660 27660
Gas data1)
1) Hi 15 °C - 1013 mbar - dry: Natural gas 34.02 MJ/m
3(9.5 kWh/m 3)
LPG: Butane 45.65 MJ/kg (12.7 kWh/kg) - Propane 46.34 MJ/kg (12.9 kWh/kg)
Supply pressure
02GHsaglarutaN kPa 2 2 2
03G)enaporP/enatuB(GPL kPa 2,8 2,8 2,8
Consumption
02GHsaglarutaN m3/h2,2 2,77 3,5
03G)enaporP/enatuB(GPL Kg/h 1,75 2,2 2,79
Number of injectors 12 14 18
Water data
Maximum permissible pressure
2)
2) Considering the water dilution eectthis value must not be exceeded.
pw psi 170 170 170
Temperature selector in fully clockwise position
Temperature rise °C 50 50 50
Flow range l/min 2 - 5,5 2,0 - 7 2,0 - 8,8
nimwperusserpgnitarepomuminiM psi 1,5 1,5 3,0
Minimum pressure for maximum water ow psi 3,6 5,0 7,2
Temperature selector in fully anti-clockwise position
Temperature rise °C 25 25 25
Flow range l/min 4 - 11 4 - 14 4 - 17,6
Minimum pressure for maximum water ow psi 8,7 14,5 19
Combustion products
3)
3) For nominal caloric power.
Minimum low pressure mbar 0,015 0,015 0,015
Flow g/s 13 17 22
Temperature °C 160 170 180
Table 6

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Use | 9
3 Use
3.1 Before starting up the heater
Check if the gas indicated on the rating plate is the same as
the one used at the location.
Open the gas valve.
Open the water valve.
3.2 Batteries
Battery insertion
Insert the two 1.5 V R20 batteries.
Fig. 3 Inserting the batteries
Replacing the batteries
The batteries must be changed ifthe red LED starts ashing.
Fig. 4 Replacing the batteries
Precautions when using the batteries
•Do not dispose of batteries asdomestic waste. Take them
to appropriate collecting places for recycling.
•Do not insert at batteries.
•Only use the type of batteries indicated.
3.3 Turning the heater on and o
Turning on
Press the switch , position .
Fig. 5
Green light on = Main burner on
Open all water and gas blocking devices.
Purge the pipes.
CAUTION:
The front panel in the burner and pilot burner
area may reach high temperatures, with risk of
burning in case of contact
CAUTION:
Initial startup must be performed by a
qualied technician who will provide the
client with all the necessary information
for optimum operation of the gas heater.
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6720648592 (2014/05)
10 | Use
Fig. 6
Turning o
Press the switch , position .
3.4 Power adjustment
Lower water temperature.
Less power.
Fig. 7
Higher water temperature.
More power.
Fig. 8
3.5 Temperature/ow adjustment
Turn anti-clockwise
Increases ow and decreases water temperature.
Fig. 9
Turn clockwise.
Decreases ow and increases water temperature.
Regulating the temperature tothe minimum required value
reduces energy consumption as well as the possibility of
limescale deposits inthe heat exchanger.
3.6 Purge the appliance
If there is a risk of freezing, proceed as follows:
Remove the retaining clip from threaded bushing (Fig. 10,
[1]).
Remove threaded bushing (Fig. 10,[2]) from water valve.
6720680412-03.1av