Greenstar 24i jjuunniioorr / 28i jjuunniioorrWALL HUNG GAS-FIRED CONDENSING COMBINATION BOILERFOR SEALED CENTRAL HEATING SYSTEMS & DOMESTIC HOT WATER

USER INSTRUCTIONS &CUSTOMER CARE GUIDE

THIS APPLIANCE IS FOR USE WITHNATURAL GAS OR LPG (Cat II 2H3P TYPE C13 & C33)

24i junior NATURAL GAS: 47 311 86

24i junior LIQUID PETROLEUM GAS: 47 311 90

28i junior NATURAL GAS: 47 311 87

28i junior LIQUID PETROLEUM GAS: 47 311 91

CONTACT INFORMATION

WORCESTER BOSCH:

TECHNICAL: 08705 266241

SERVICE: 08457 256206

SPARES: 01905 752571

LITERATURE: 01905 752556

TRAINING: 01905 752526

SALES: 01905 752640

WEBSITE: www.worcester-bosch.co.uk

WATER TREATMENT:

FERNOX 01799 550811

www.fernox.com

SENTINEL 0151 420 9595

www.betzdearborn.com/sentinel

FLUE TERMINAL GUARDS:

TOWER FLUE COMPONENTS

Vale Rise, Tonbridge TN9 1TB

USER INSTRUCTIONS & CUSTOMERCARE GUIDE

PLEASE READ THESE INSTRUCTIONSCAREFULLY BEFORE OPERATING YOURAPPLIANCE

THESE INSTRUCTIONS ARE APPLICABLE TOTHE WORCESTER BOSCH APPLIANCEMODEL(S) STATED ON THE FRONT COVER OFTHIS MANUAL ONLY AND MUST NOT BE USEDWITH ANY OTHER MAKE OR MODEL OFAPPLIANCE.

THE INSTRUCTIONS APPLY IN THE UK ONLYAND SHOULD BE FOLLOWED EXCEPT FORANY STATUTORY OBLIGATION.

IF YOU ARE IN ANY DOUBT CONTACT THEWORCESTER BOSCH TECHNICAL HELPLINE.

DISTANCE LEARNING AND TRAININGCOURSES ARE AVAILABLE FROMWORCESTER BOSCH.

THIS APPLIANCE MUST BE INSTALLED BY ACOMPETENT PERSON. FAILURE TO INSTALLCORRECTLY COULD LEAD TO PROSECUTION.

PLEASE LEAVE THIS GUIDE, THEINSTALLATION INSTRUCTIONS AND THECOMPLETED BENCHMARK LOG BOOK WITHTHE USER OR AT THE GAS METER AFTERINSTALLATION.

ABBREVIATIONS USED IN THIS BOOK:

NG - Natural Gas

LPG - Liquid Petroleum Gas

CH - Central Heating

SEDBUK - Seasonal Efficiency of DomesticBoilers in the United Kingdom

USER INSTRUCTIONS &CUSTOMER CARE GUIDE

WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

CONTENTSWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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CONTENTS

INTRODUCTIONEXCELLENCE COMES AS STANDARD 2

SAFETY PRECAUTIONS 3

GENERAL NOTES 4

USING YOUR APPLIANCECONTROLS 6

OPERATING THE APPLIANCE 7

Switching the appliance on/off 7

Setting the central heating temperature 7

Controlling central heating 7

Frost protection 7

Controlling domestic hot water 8

Fault condition 9

ENERGY SAVINGTIPS ON ENERGY SAVING 10

MAINTENANCEMAINTAINING YOUR APPLIANCE 13

FAULT FINDING 14

FAULT OR BREAKDOWN 15

GUARANTEEYOUR GUARANTEE 16

GUARANTEE REGISTRATION 17

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EXCELLENCE COMES AS STANDARD WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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EXCELLENCE COMES AS STANDARD

Thank you for purchasing a Greenstar 24i Junior/ 28i Junior gas-fired condensing combinationboiler manufactured by Worcester Bosch. Thecompany prides itself on manufacturing boilersto the strictest quality control standardsthroughout every stage of production.Worcester Bosch has led the field in innovativeappliance design and performance for morethan 40 years. This heritage means all productsare of exceptional quality and proven reliability.

The Greenstar range in particular is extremelyenergy efficient, converting up to 97% of gasconsumed into heat, offering you economicalrunning costs and value for money. It sits inSEDBUK Band A, and is therefore amongst thetop energy rated appliances available.

There is also the reassurance of our no-nonsense 2 years parts and labour guarantee -backed up by Worcester Total Cover, anoptional complete maintenance scheme to keepyour boiler operating at peak condition andefficiency.

To find out more about Worcester Bosch logonto www.worcester-bosch.co.uk .

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SAFETY PRECAUTIONSWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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IF YOU SMELL GAS:

DO NOT operate any electrical switches

Extinguish any naked flame

Turn off the gas service cock at the meter

Open windows and doors

Telephone your gas company

IF YOU SMELL FUMES FROM THE APPLIANCE:

Switch off the appliance, as shown in Fig. a.

Open windows and doors.

BENCHMARK STANDARD

‘Benchmark’ is a code of practice for correctlyinstalling, commissioning and servicing ofdomestic water heating appliances.

A Benchmark Log Book is provided by themanufacturer for the installer to complete ALLdetails together with their CORGI registrationnumber and sign to confirm that the boiler hasbeen installed and commissioned according tothe manufacturer’s instructions.

IMPORTANT: The completed Benchmark LogBook will be required in the event of anywarranty work and may be required by the localBuilding Control Inspector.

HEALTH & SAFETY

The appliance contains no asbestos and nosubstances used in the construction processthat contravene the COSHH Regulations(Control of Substances Hazardous to HealthRegulations 1988).

COMBUSTIBLE AND CORROSIVE MATERIALS

Do not store or use any combustible materials(paper, thinners, paints etc.) inside or within thevicinity of the appliance.

Chemically aggressive substances, such ashalogenated hydrocarbons containing chlorineor fluorine compounds can corrode theappliance and invalidate any warranty.

FITTING & MODIFICATIONS

Fitting the appliance, any controls to theappliance and removal of the outer casing mayonly be carried out by a competent engineer inaccordance with the Gas Safety (Installationand Use) Regulations.

Flue systems must not be modified in any wayother than as described in the Installationinstructions and any misuse or unauthorisedmodifications to the appliance, flue orassociated components and systems couldinvalidate the warranty. The manufactureraccepts no liability arising from any suchactions. This does not affect your statutoryrights.

SERVICING

The user is recommended to have the systemregularly serviced by a competent, qualifiedengineer (such as British Gas or CORGIregistered personnel) using original spares, tohelp maintain the economy, safety and reliabilityof the appliance and to have the ServiceRecord completed in the Benchmark Log Book.

The appliance should be serviced annually afterinstallation unless the particular installationconditions and usage demand more frequentservices.

IMPORTANT - ensure that the service engineercompletes the Service Record in theBenchmark Log Book after each service.

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Fig. a.

PUSH

GENERAL NOTES WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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To get the best from your appliance please readthese instructions carefully.

SEALED HEATING SYSTEMS

This appliance is fitted to a sealed heatingsystem which is pre-pressurised. Your installerwill advise you of the minimum and maximumpressure which should be indicated on thepressure gauge.

Check regularly that the pressure is maintainedand contact your installer or maintenanceengineer if a permanent significant drop inpressure is indicated on the pressure gauge. Ifthe system loses pressure it should be re-pressurised and the cause of the fallinvestigated.

CENTRAL HEATING SYSTEMS

During the first few hours of operation of thecentral heating system, check that all radiatorsare being heated at an even rate. If the top of aradiator is at a lower temperature than thebottom then it should be vented by releasing airthrough the venting screw at the top of theradiator. Ask your installer to show you how thisis done.

This boiler is fitted to a sealed system; repeatedventing will reduce the quantity of water in thesystem and this must be replenished for safeand satisfactory operation of the appliance.

Should water leaks be found in the system or ifexcessive venting is required, then a serviceengineer must be contacted to inspect theinstallation and rectify any fault.

Only additives that are compatible withaluminium may be used in the system. Anyincompatible additive used will invalidate theguarantee.

CONDENSATE DRAIN

This is a condensing appliance and the terminalwill, at times give out a plume of water vapour.This is quite normal.

The appliance also produces quantities ofcondensate which is discharged regularly by asiphon within the boiler via a pipe to drain. Thispipe must not be blocked or altered in any way.

CLEARANCES - VENTILATED COMPARTMENT

Your installer will have provided adequatespace around the appliance for safety andservicing access. Do not restrict this space withthe addition of cupboards, shelves etc. next tothe appliance.

GENERAL NOTES

ROOM THERMOSTAT

A room temperature controller and programmershould be fitted to control the central heating.Refer to the instructions supplied with thethermostat for information on siting and setting.

THERMOSTATIC RADIATOR VALVES

It is recommended that this type of valve isfitted to all but one of the radiators (or at leastthose in the sleeping accommodation). Theremaining radiator, which must be where theroom thermostat is located, should be un-controlled and must be left open. Thethermostatic radiator valves should conform tothe requirements of BS2767:10.

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1450mm

mm mm

+ 30mmabove elbow

5mm

5mm

600mm

+ 30mmabove elbow

200mm*

200mm*

100mm**600mm***

200mm

200mm

*600mm(**25mm)

*600mm service clearance required to a fixed surface(**25mm from removable door or panel)

SAFETY PRECAUTIONSWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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BOILER CLEARANCES - UNVENTILATEDCOMPARTMENT

The diagram opposite shows the minimumspace required to install and service the boilerinside an unventilated compartment.

** Space required for unventilated areas with aremovable door or panel.

*** 600mm clearance required to a fixedsurface for servicing.

* This space can be reduced to 50mm for oneside only provided that the total side clearancesadd up to 400mm or more.

VENTILATION

This is a room sealed appliance and does notrequire any air for combustion from inside theproperty. If the appliance is fitted into acupboard or a compartment is built around theappliance after installation, then thecompartment must be separated from the boilerspace by a perforated non-combustible partitionas described in BS 6798.

Notwithstanding the requirements of BS 6798and BS 5440 there is no need for ventilationopenings to be provided in the compartmentbecause of the low heat loss from the appliancecasing, if the clearances shown are maintained.

Do not operate the appliance if the flue terminalfitted on the outside wall or roof is obstructedor damaged.

PUMP ANTI-SEIZURE

If there has been no heating demand for 24hours the boiler will run the system pump for afew seconds to reduce the possibility of pumpseizure during long periods of inactivity, whichis usually more frequent during the summermonths.

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mm mm

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600mm

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200mm*

200mm*

100mm**600mm***

200mm

200mm

CONTROLS WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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CONTROLS

1. MASTER SWITCH FOR ON/OFF

2. CENTRAL HEATINGTEMPERATURE CONTROL

3. MAINS ON/OFF INDICATOR + FAULTDIAGNOSTIC LIGHT

4. BURNER ON INDICATOR LIGHT (GREEN)

5. ECO BUTTON (DOMESTIC HOT WATER PRE-HEAT ON/OFF)

6. FAULT RESET BUTTON

7. SYSTEM PRESSURE GAUGE

8. POSITION FOR OPTIONAL PROGRAMMER

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OPERATING THE APPLIANCEWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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SWITCHING THE APPLIANCE ON/OFF

Switching on

Switch on the appliance by pressing the master switch.

The indicator light shows blue

Switching off

Switch off the appliance by pressing the master switch.

The blue indicator light goes out.

SETTING THE CENTRAL HEATING TEMPERATURE

Turn the central heating temperature control to the desired level, between 40°C and 82°C

When the burner is lit, the green indicator lightunderneath the on/off switch is illuminated.

CONTROLLING CENTRAL HEATING

Set the timer to the correct time.

Set room thermostat to the desired room temperature.

Set the thermostatic radiator valves to the desired settings.

FROST PROTECTION

Leave master switch on.

Turn the central heating temperature control to.

If the temperature falls to 5°C within the boiler itwill fire to avoid the possibility of freezing.

Add a suitable anti-freeze fluid to the water inthe central heating system.

If remote pipework is likely to be subjected tofreezing conditions, ensure the installer has fitted a frost thermostat in the area to protectthe pipework.

OPERATING THE APPLIANCE

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HOT WATER TEMPERATURE

The hot water temperature is fixed at 55°C andcan not be adjusted.

DOMESTIC HOT WATER PRE-HEAT

Pre-heat reduces the time taken to produce hotwater at the tap and is controlled by the ECObutton.

Press the ECO button to select either:

When the ECO button is not illuminated the boiler will be in pre-heat mode (which willreduce the time taken to produce hot water atthe tap).

OR

When the ECO button is illuminated the boilerwill be in ECO mode with no pre-heat available.

OPERATING THE APPLIANCE

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OPERATING THE APPLIANCE WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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FAULT CONDITION

In the unlikely event of a fault occurring whilethe appliance is in operation:

The reset button will flash once per second andthe mains indicator (blue light) will flash at differentspeeds dependent on fault.

To reset boiler press the reset button.

The reset button will no longer be illuminatedand the mains indicator will stop flashing.

The boiler will function normally, dependent onprogrammer and room thermostat settings.

If the fault remains and cannot be cleared bypressing the reset button, or if fault persistscontact Worcester Bosch for assistance, givinga description of the fault and, if possible, thefault flashing sequence from the mainsindicator.

OPERATING THE APPLIANCE

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OPERATING THE APPLIANCEWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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Heating economically

The boiler is designed to provide a high level ofcomfort while keeping gas consumption and theresulting environmental effect as low aspossible. The gas supply to the burner iscontrolled according to the level of demand forheat. The boiler continues to operate with a lowflame if the demand for heat reduces. Thetechnical term for this process is modulatingcontrol. Modulating control reducestemperature fluctuations and provides evendistribution of heat throughout the home. Thismeans that the boiler may stay on for relativelylong periods but will use less gas than anappliance that continually switches on and off.

Central heating systems with roomthermostats/thermostatic radiator valves

The central heating control on the boiler shouldbe set to the maximum rated temperature of thecentral heating system.

The temperature of each room can be setindividually (except primary room with the roomthermostat) using the thermostatic radiatorvalves.

TIPS ON ENERGY SAVING

TIPS ON ENERGY SAVING WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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Roof insulation

Around 30% of the heat loss from a property isthrough the roof. Replace any old insulationwith new insulation, preferably of around200mm thickness or more.

Window frames

Single glazed windows, particularly those withsteel frames, can lose a great deal of heat.Consideration should be given to replacementwith PVCu or wooden framed double glazedunits.

Curtains

Lined curtains, or heavier full length curtainscan provide excellent insulation. However,always ensure that the curtains do not drapeover radiators.

Draughts

Try to ensure that draughts around doors,windows, letterboxes and keyholes etc. arereduced by using a suitable draught excluder.Warning - Do not block or seal any air ventsthat are installed to ensure the central heatingboiler operates safely.

Room thermostats

Reducing the setting of the room thermostat by1°C can reduce fuel consumption by up to 10%.

New control systems

Upgrade your heating control system ifnecessary with the latest equipment available.The minimum level of control is a programmer,interlocking room thermostat and thermostaticradiator valves.

TIPS ON ENERGY SAVING

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Radiators

More often than not radiators will be sitedunderneath a window, so the warm air from theradiator heats the colder incoming air from thewindow. The performance of the radiator will beaffected if the curtains are allowed to drapeover the radiator or shelves are fitted above it.The positioning of furniture and tables in frontof the radiator should also be avoided.

It is advisable to manually adjust all radiatorthermostatic valves every 2-3 months to preventthem sticking. It is also important that theplastic tops of all valves are always in positionand not cracked or damaged to preventaccidents. Care should be taken when vacuumcleaning carpets to avoid damage to valves andpipework.

The heating system and the outputs of theradiators have been carefully selected by yourinstaller. The temperature obtainable in anygiven room is dependent on all radiators beingoperated at the same time. If you decide to turnoff radiators in unused rooms, spare bedroomsetc., you may experience slightly lower roomtemperatures in rooms adjacent to unheatedrooms.

TIPS ON ENERGY SAVING

TIPS ON ENERGY SAVING WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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Your new Greenstar 24i Junior / 28i Junior gas-fired appliance represents a long terminvestment in a reliable, high quality product.

In order to realise its maximum working life, andto ensure it continues to operate at peakefficiency and performance, it is essential thatyour boiler receives regular servicing andmaintenance checks from a competent personbeyond the initial 2 year guarantee period.

If you would like to know more about aWorcester Bosch service contract, please tickthe appropriate box on your warrantyregistration card.

If your Greenstar 24i Junior / 28i Junior shouldfail to operate correctly or requires servicingplease contact the Worcester Bosch ServiceDepartment (see inside front cover for details).

Details of the boiler including the Gas Councilnumber can be found under the controls coverflap on the boiler.

MAINTAINING YOUR APPLIANCE

MAINTAINING YOUR APPLIANCEWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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FAULT FINDING

Problem Cause Remedy

Switch off appliance atmaster switch, wait a fewseconds then switch onagain

Check setting

Reduce flow rate at tap

Desired roomtemperature is notreached

Thermostatic radiatorvalve(s) set too low

Temperature control forCH flow on boiler set toolow

Air trapped in heatingsystem

Desired roomtemperature exceeded bylarge amount

Heating stays on for toolong

No on/off indicator

Hot water temperaturetoo low

Radiators are too hot

Clock is incorrectly set

Momentary power failure

Programmer setting

Water flow at tap too high

Increase thermostaticradiator valve setting(s)

Increase CH flowtemperature controlsetting

Bleed radiators andrecharge heating system

Turn down thermostaticradiator valves / roomthermostat

Reduce central heatingtemperature on boiler

Check setting

FAULT FINDING WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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This table gives information on basic operatingsystem problems.

In the unlikely event of a boiler fault please readthe following page thoroughly before contactingWorcester Bosch.

This appliance is supported in the UK byWorcester, Bosch Group.

Specialist factory trained Service Engineers areavailable to attend a breakdown occurring onthis appliance.

No charge will be made for parts and/orlabour providing:

An appliance fault is found and the appliancehas been installed within the past 24 months.Reasonable evidence of this must be suppliedon request. i.e. the Benchmark Logbook

A call-out charge will be made where:

The appliance has been installed for over 24 months

OR

Our Field Service Engineer finds no fault withthe appliance (see Note).

OR

The cause of breakdown is misuse or with other parts of your plumbing/heating system, or with equipment not supplied by WorcesterBosch.

Note. NO APPLIANCE FAULT IS FOUND ONOVER 30% OF ALL SERVICE CALL OUTS.

Please read this guide carefully to gain a goodunderstanding of the operation of yourappliance. In the case of a suspected fault,refer to the fault finding section of this guide.

If in doubt contact our Technical Helpline

In the event of an appliance fault or breakdownplease contact our Service Department. Yourservice administrator will arrange for anengineer to call with the minimum of delay;under normal circumstances this will be from 1- 3 working days (excluding weekends) forpriority breakdown situations (no hot waterand/or heating).

Invoices for attendance and repair work carriedout on this appliance by any third party will notbe accepted.

FAULT OR BREAKDOWN

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This appliance is guaranteed against faultymaterial or workmanship for a period of 2 yearsfrom the date of installation subject to thefollowing terms and conditions.

During the period of this guarantee any components of the unit which are proven to be faulty or defective in manufacture will be exchanged or repaired free of charge by Worcester Bosch.

The householder may be asked to prove the date of installation, that the appliance was correctly commissioned and, where appropriate, the first year’s service has been carried out to the satisfaction of Worcester Bosch when requested. These should be part of the Benchmark Logbook.

Any product or part returned for servicing under the guarantee must be accompanied by a claim stating the model, serial number &date of installation.

Worcester Bosch will not accept responsibility for damage caused by faulty installation, neglect, misuse or accidental damage or the non-observance of the instructions contained in the Installation and Servicing Manual and User Instructions.

The appliance has been used only for the normal domestic purposes for which it was designed.

This guarantee applies only to equipment purchased and used in the United Kingdom.

This guarantee does not affect your statutoryrights.

YOUR GUARANTEE

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YOUR GUARANTEE WORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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You should complete and return the postpaidGuarantee Registration Card within 14 days ofpurchase.

Returning the card will register you as theowner of your new Greenstar 24i Junior / 28iJunior appliance and will assist us inmaintaining an effective and efficient customerservice by establishing a reference andpermanent record for your boiler.

This does not affect your statutory rights.

For your own record:

Check that the Benchmark “Log Book” hasbeen completed by your installer or serviceengineer.

GUARANTEE REGISTRATION

Model

Serial No.(See guarantee card)

Type / size

Date of installation

GUARANTEE REGISTRATIONWORCESTER BOSCH GREENSTAR 24i/28i Junior8 716 107 338a (11.04)

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USER INSTRUCTIONS &CUSTOMER CARE GUIDE

Worcester, Bosch Group

Cotswold Way, Warndon, Worcester WR4 9SW.

Tel. 01905 754624 Fax. 01905 754619

www.worcester-bosch.co.uk

Worcester Bosch Group is a trading name of BBT Thermotechnology UK Ltd.

8 716 107 338a (11.04)