Bosch Appliances Boiler 24i junior User Manual

USER INSTRUCTIONS &  
CUSTOMER CARE GUIDE  
Greenstar 24i junior / 28i junior  
WALL HUNG GAS-FIRED CONDENSING COMBINATION BOILER  
FOR SEALED CENTRAL HEATING SYSTEMS & DOMESTIC HOT WATER  
THIS BOILER IS USED WITH  
NATURAL GAS OR LPG (Cat II 2H3P TYPE C13, C33 & C53)  
NATURAL GAS 24i junior GC NUMBER: 47 311 86  
28i junior GC NUMBER: 47 311 87  
LIQUID PETROLEUM GAS 24i junior GC NUMBER: 47 311 90  
28i junior GC NUMBER: 47 311 91  
CONTENTS  
INTRODUCTION  
DEDICATED TO HEATING COMFORT  
SAFETY PRECAUTIONS  
GENERAL NOTES  
1
2
3
USING YOUR BOILER  
CONTROLS  
6
7
7
7
7
7
8
9
OPERATING THE BOILER  
Switching the boiler on/off  
Setting the central heating temperature  
Controlling central heating  
Frost protection  
Controlling domestic hot water  
Fault condition  
MAINTENANCE  
MAINTAINING YOUR BOILER  
FAULT FINDING  
FAULT OR BREAKDOWN  
10  
11  
12  
ENERGY SAVING  
TIPS ON ENERGY SAVING  
13  
GUARANTEE  
YOUR GUARANTEE  
GUARANTEE REGISTRATION  
15  
16  
Dedicated to heating comfort  
Thank you for purchasing a Greenstar gas-fired condensing combination boiler  
manufactured by Worcester, Bosch Group. The company prides itself on manufacturing  
boilers to the strictest quality control standards throughout every stage of production.  
Worcester, Bosch Group has led the field in innovative boiler design and performance  
for more than 40 years. This heritage means all products are of exceptional quality and  
proven reliability.  
The Greenstar range in particular is extremely energy efficient, offering you economical  
running costs and value for money. It sits in SEDBUK Band A, and is therefore  
amongst the top energy rated boilers available.  
There is also the reassurance of our no-nonsense 2 years parts and labour guarantee -  
backed up by Worcester Total Cover, an optional complete maintenance scheme to  
keep your boiler operating at peak condition and efficiency.  
1
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
CONTENTS  
SAFETY PRECAUTIONS  
IF YOU SMELL GAS!  
DO NOT SMOKE OR STRIKE MATCHES  
DO NOT TURN ELECTRICAL SWITCHES ON OR OFF  
PUT OUT NAKED FLAMES  
OPEN DOORS AND WINDOWS  
KEEP PEOPLE AWAY FROM THE AREA AFFECTED  
TURN OFF THE CONTROL VALVE AT THE METER  
CALL YOUR GAS COMPANY  
BOILER OPERATION:  
This boiler must only be operated by a responsible adult who  
has been instructed in, understands and is aware of the  
boiler’s operating conditions and effects.  
COMBUSTIBLE AND CORROSIVE MATERIALS  
Do not store or use any combustible materials (paper, thinners, paints etc.) inside or  
within the vicinity of the boiler.  
Chemically aggressive substances can corrode the boiler and invalidate any warranty.  
FITTING & MODIFICATIONS  
Fitting the boiler, any controls to the boiler and removal of the outer casing may only  
be carried out by a competent engineer in accordance with the Gas Safety  
(Installation and Use) Regulations.  
Flue systems must not be modified in any way other than as described in the  
Installation instructions and any misuse or unauthorised modifications to the boiler,  
flue or associated components and systems could invalidate the warranty. The  
manufacturer accepts no liability arising from any such actions. This does not affect  
your statutory rights.  
2
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
EXCELLENCE COMES AS STANDARD  
8 716 115 661 (05/2009)  
GENERAL NOTES  
SERVICING  
The boiler must be serviced regularly by a competent, qualified person, such as a  
Worcester service engineer or alternatively a British Gas or other Gas Safe registered  
person.  
Always use original spares, to help maintain the economy, safety and reliability of the  
boiler and to have the Service Record completed in the Benchmark checklist.  
IMPORTANT:  
Ensure that the service engineer completes the Service Record in  
the Benchmark checklist after each service.  
The completed Benchmark checklist will be required in the event of  
any warranty work and may be required by the local Building Control  
Inspector.  
NOTE:  
The Benchmark checklist and service interval record can be found at  
the rear of the Installation, Commissioning and Servicing  
Instructions.  
BENCHMARK STANDARD  
‘Benchmark’ is a code of practice for correctly installing, commissioning and servicing  
of domestic water heating boilers.  
A Benchmark Checklist is provided by the manufacturer for the installer to complete  
ALL details together with their Gas Safe registration number and sign to confirm that  
the boiler has been installed and commissioned according to the manufacturer’s  
instructions.  
HEALTH & SAFETY  
The boiler contains no asbestos and no substances used in the construction process  
that contravene the COSHH Regulations (Control of Substances Hazardous to Health  
Regulations 1988).  
3
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
SAFETY PRECAUTIONS  
GENERAL NOTES  
To get the best from your boiler please  
read these instructions carefully.  
SEALED HEATING SYSTEMS  
CLEARANCES - VENTILATED  
COMPARTMENT  
This boiler is fitted to a sealed heating  
system which is pre-pressurised. Your  
installer will advise you of the minimum  
and maximum pressure which should be  
indicated on the pressure gauge.  
Your installer will have provided adequate  
space around the boiler for safety and  
servicing access. Do not restrict this  
space with the addition of cupboards,  
shelves etc. next to the boiler.  
Check regularly that the pressure is  
maintained and contact your installer or  
maintenance engineer if a permanent  
significant drop in pressure is indicated  
on the pressure gauge. If the system  
loses pressure it should be re-pressurised  
and the cause of the fall investigated.  
+ 30mm  
above elbow  
CENTRAL HEATING SYSTEMS  
During the first few hours of operation of  
the central heating system, check that all  
radiators are being heated evenly. If the  
top of a radiator is at a lower temperature  
than the bottom then it should be vented  
by releasing air through the venting screw  
at the top of the radiator. Ask your  
5mm  
5mm  
25mm*  
600mm**  
installer to show you how this is done.  
This boiler is fitted to a sealed system;  
repeated venting will reduce the quantity  
of water in the system and this must be  
replenished for safe and satisfactory  
operation of the boiler.  
200mm  
*600mm service clearance required to a fixed surface  
(**25mm from removable door or panel)  
Should water leaks be found in the  
system or if excessive venting is required,  
then a service engineer must be  
contacted to inspect the installation and  
rectify any fault.  
ROOM THERMOSTAT  
A room temperature controller and  
programmer should be fitted to control the  
central heating. Refer to the instructions  
supplied with the thermostat for  
Only additives that are compatible with  
aluminium may be used in the system. Any  
incompatible additive used will invalidate  
the guarantee.  
information on siting and setting.  
THERMOSTATIC RADIATOR VALVES  
CONDENSATE DRAIN  
It is recommended that this type of valve is  
fitted to all but one of the radiators (or at  
least those in the sleeping  
accommodation). The remaining radiator,  
which must be where the room thermostat  
is located, should be un-controlled and  
must be left open. The thermostatic  
radiator valves should conform to the  
requirements of BS2767:10.  
This is a condensing boiler and the  
terminal will, at times give out a plume of  
water vapour. This is quite normal.  
The boiler also produces quantities of  
condensate which is discharged regularly  
by a syphon within the boiler via a pipe to  
drain. This pipe must not be blocked or  
altered in any way.  
4
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
GENERAL NOTES  
GENERAL NOTES  
BOILER CLEARANCES -  
UNVENTILATED COMPARTMENT  
+ 30mm  
above elbow  
The diagram opposite shows the  
minimum space required to install and  
service the boiler inside an unventilated  
compartment.  
200mm*  
** Space required for unventilated areas  
with a removable door or panel.  
200mm*  
*** 600mm clearance required to a fixed  
surface for servicing.  
100mm**  
600mm***  
* The boiler must have more clearance in  
the unventilated compartment compared  
to the ventilated compartment.  
Two examples are shown opposite, refer  
to the “Installation, commissioning and  
servicing instruction manual” for further  
information.  
Do not add cupboards, shelves etc. to  
restrict the space around the boiler.  
200mm  
VENTILATION  
This is a room sealed boiler and does not  
require any air for combustion from inside  
the property. If the boiler is fitted into a  
cupboard or a compartment is built  
around the boiler after installation, then  
the compartment must be separated from  
the boiler space by a perforated non-  
combustible partition as described in BS  
6798.  
Notwithstanding the requirements of BS  
6798 and BS 5440 there is no need for  
ventilation openings to be provided in the  
compartment because of the low heat  
loss from the boiler casing, if the  
**  
***  
clearances shown are maintained.  
Do not operate the boiler if the flue  
terminal fitted on the outside wall or roof  
is obstructed or damaged.  
PUMP ANTI-SEIZURE  
If there has been no heating demand for  
24 hours the boiler will run the system  
pump for a few seconds to reduce the  
possibility of pump seizure during long  
periods of inactivity, which is usually more  
frequent during the summer months.  
5
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
SAFETY PRECAUTIONS  
CONTROLS  
To gain access to the boiler controls  
push at the top of the flap and release.  
7
3
4
5
6
1. CENTRAL HEATING  
TEMPERATURE CONTROL  
2. MAINS ON/OFF INDICATOR +  
FAULT DIAGNOSTIC LIGHT  
3. BURNER ON INDICATOR LIGHT  
(GREEN)  
4. ECO BUTTON (DOMESTIC HOT  
WATER PRE-HEAT ON/OFF)  
5. FAULT RESET BUTTON  
6. SYSTEM PRESSURE GAUGE  
7. POSITION FOR OPTIONAL  
PROGRAMMER  
1
2
6
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
CONTROLS  
OPERATING THE BOILER  
SWITCHING THE BOILER ON/OFF  
Switching on  
Switch on the boiler at the mains supply,  
the indicator light shows blue. There  
should be no need to switch the boiler off  
unless, in the unlikely event, a fault has  
occurred.  
Switching off  
Should you need to switch off the boiler  
then do so at the mains supply. The blue  
indicator light goes out.  
NOTE: When the boiler is switched off  
frost protection is disabled.  
SETTING THE TEMPERATURE  
Turn the temperature control knob to  
the desired level, approximate  
temperatures for each setting are shown  
in the table opposite.  
When the burner is lit, the green burner  
on indicator light is illuminated.  
40°C  
47°C  
53°C  
61°C  
68°C  
74°C  
80°C  
82°C  
Min ---  
1
2
3
4
5
6
---  
---  
---  
---  
---  
---  
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.  
Max ---  
FROST PROTECTION  
In the event where the boiler is not to be  
used for a period of time, leave power on  
and turn the temperature control to  
.
If the temperature falls below 5°C within  
the boiler it will periodically fire to avoid  
the possibility of freezing.  
If remote pipework is exposed to  
low temperatures, ensure that the  
installer has added a frost  
thermostat.  
7
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
OPERATING THE BOILER  
OPERATING THE BOILER  
HOT WATER TEMPERATURE  
The hot water temperature is fixed at  
55°C and can not be adjusted.  
DOMESTIC HOT WATER PRE-HEAT  
Pre-heat reduces the time taken to  
produce hot water at the tap and is  
controlled by the ECO button.  
Press and hold the ECO button to  
select either, not illuminated or  
illuminated:  
When the ECO button is not  
illuminated the boiler will be in pre-  
heat mode (which will reduce the time  
taken to produce hot water at the tap).  
OR  
When the ECO button is illuminated  
the boiler will be in ECO mode with no  
pre-heat available.  
8
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
OPERATING THE BOILER  
OPERATING THE BOILER  
FAULT CONDITION  
In the unlikely event of a fault occurring  
while the boiler is in operation:  
The reset button will flash once per  
second and the mains indicator (blue  
light) will flash at different speeds  
dependent on fault.  
To reset boiler press the reset  
button.  
The reset button will no longer be  
illuminated and the mains indicator will  
stop flashing.  
The boiler will function normally,  
dependent on programmer and room  
thermostat settings.  
If the electrical power to the boiler has  
been interrupted a “reset fault”  
condition will exist. Reset the boiler as  
described above.  
If the fault remains and cannot be  
cleared by pressing the reset button, or  
if fault remains call:  
Worcester, Bosch Group for  
assistance, giving a description of  
the fault and, if possible the fault  
flashing sequence from the mains  
indicator.  
9
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
OPERATING THE BOILER  
MAINTAINING YOUR BOILER  
Your new Greenstar gas-fired boiler represents a long term investment in a reliable, high  
quality product.  
In order to realise its maximum working life, and to ensure it continues to operate at  
peak efficiency and performance, it is essential that your boiler receives regular  
servicing and maintenance checks from a competent person beyond the initial 2 year  
guarantee period.  
If you would like to know more about a Worcester, Bosch Group service contract,  
please tick the appropriate box on your warranty registration card.  
If your Greenstar gas-fired boiler should fail to operate correctly or requires servicing  
please contact the Worcester, Bosch Group Service Department (see inside front cover  
for details).  
Details of the boiler including the Gas Council number can be found under the controls  
cover flap on the boiler.  
10  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
MAINTAINING YOUR BOILER  
8 716 115 661 (05/2009)  
FAULT FINDING  
This table gives information on basic operating system problems.  
In the unlikely event of a boiler fault please read the following page thoroughly  
before contacting Worcester, Bosch Group.  
Problem  
Cause  
Remedy  
Desired room  
temperature is not  
reached  
Thermostatic radiator  
valve(s) set too low  
Increase thermostatic  
radiator valve setting(s)  
Temperature control for  
CH flow on boiler set too  
low  
Increase CH flow  
temperature control  
setting  
Air trapped in heating  
system  
Bleed radiators and  
recharge heating system  
Desired room  
temperature exceeded by  
large amount  
Radiators are too hot  
Turn down thermostatic  
radiator valves / room  
thermostat  
Reduce central heating  
temperature on boiler  
Heating stays on for too  
long  
Clock is incorrectly set  
Momentary power failure  
Check setting  
No on/off indicator light  
Switch off boiler at the  
mains supply, wait a few  
seconds then switch on  
again  
Check setting  
Hot water temperature  
too low  
Programmer setting  
Reduce flow rate at tap  
Water flow at tap too high  
11  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
FAULT FINDING  
FAULT OR BREAKDOWN  
This boiler is supported in the UK and Eire by Worcester, Bosch Group.  
Specially trained, Worcester, Bosch Group Service Engineers are available to attend a  
breakdown occurring on this boiler.  
No charge will be made for parts and/or labour providing:  
An boiler fault is found and the boiler has been installed within the past 24 months.  
Reasonable evidence of this must be supplied on request. i.e. the Benchmark Checklist.  
A call-out charge will be made where:  
The boiler has been installed for over 24 months.  
OR  
Evidence cannot be provided that the first year service inspection has been carried  
out (i.e. an entry in the Benchmark Checklist).  
OR  
Our Field Service Engineer finds no fault with the boiler (see Note).  
OR  
The cause of breakdown is misuse or with other parts of your plumbing/heating system, or  
with equipment not supplied by Worcester, Bosch Group.  
NOTE: NO BOILER FAULT IS FOUND ON OVER 30% OF SERVICE CALL OUTS.  
Please read this guide carefully to gain a good understanding of the operation of your  
boiler. In the case of a suspected fault, refer to the fault finding section of this guide.  
If in doubt contact our Technical Support  
In the event of an boiler fault or breakdown please contact our Service Department.  
Your service administrator will arrange for an engineer to call with the minimum of delay;  
under normal circumstances this will be from 1 - 3 working days (excluding weekends)  
for priority breakdown situations (no hot water and/or heating).  
Invoices for attendance and repair work carried out on this boiler by any third party will  
not be accepted.  
12  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
FAULT OR BREAKDOWN  
8 716 115 661 (05/2009)  
TIPS ON ENERGY SAVING  
HEATING ECONOMICALLY  
The boiler is designed to provide a high level of comfort while keeping gas consumption  
and the resulting environmental effect as low as possible. The gas supply to the burner  
is controlled according to the level of demand for heat. The boiler continues to operate  
with a low flame if the demand for heat reduces. The technical term for this process is  
modulating control. Modulating control reduces temperature fluctuations and provides  
even distribution of heat throughout the home. This means that the boiler may stay on  
for relatively long periods but will use less gas than a boiler that continually switches on  
and off.  
CENTRAL HEATING SYSTEMS WITH ROOM THERMOSTATS/THERMOSTATIC  
RADIATOR VALVES  
The temperature control on the boiler should be set to the maximum rated temperature  
of the central heating system.  
The temperature of each room can be set individually (except primary room with the  
room thermostat) using the thermostatic radiator valves.  
ROOF INSULATION  
Around 30% of the heat loss from a property is through the roof. Replace any old  
insulation with new insulation, preferably of around 200mm thickness or more.  
WINDOW FRAMES  
Single glazed windows, particularly those with steel frames, can lose a great deal of  
heat. Consideration should be given to replacement with PVCu or wooden framed  
double glazed units.  
CURTAINS  
Lined curtains, or heavier full length curtains can provide excellent insulation. However,  
always ensure that the curtains do not drape over radiators.  
13  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
TIPS ON ENERGY SAVING  
TIPS ON ENERGY SAVING  
DRAUGHTS  
Try to ensure that draughts around doors, windows, letterboxes and keyholes etc. are  
reduced by using a suitable draught excluder. Warning - Do not block or seal any air  
vents that are installed to ensure the central heating boiler operates safely.  
ROOM THERMOSTATS  
Reducing the setting of the room thermostat by 1°C can reduce fuel consumption by up  
to 10%.  
NEW CONTROL SYSTEMS  
Upgrade your heating control system if necessary with the latest equipment available.  
The minimum level of control is a programmer, interlocking room thermostat and  
thermostatic radiator valves.  
RADIATORS  
More often than not radiators will be sited underneath a window, so the warm air from  
the radiator heats the colder incoming air from the window. The performance of the  
radiator will be affected if the curtains are allowed to drape over the radiator or shelves  
are fitted above it. The positioning of furniture and tables in front of the radiator should  
also be avoided.  
It is advisable to manually adjust all radiator thermostatic valves every 2-3 months to  
prevent them sticking. It is also important that the plastic tops of all valves are always in  
position and not cracked or damaged to prevent accidents. Care should be taken when  
vacuum cleaning carpets to avoid damage to valves and pipework.  
The heating system and the outputs of the radiators have been carefully selected by  
your installer. The temperature obtainable in any given room is dependent on all  
radiators being operated at the same time. If you decide to turn off radiators in unused  
rooms, spare bedrooms etc., you may experience slightly lower room temperatures in  
rooms adjacent to unheated rooms.  
14  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
TIPS ON ENERGY SAVING  
8 716 115 661 (05/2009)  
YOUR GUARANTEE  
This boiler is guaranteed against faulty material or workmanship for a period of 2 years  
from the date of installation subject to the following terms and conditions:  
Your Guarantee Registration Card must be returned within 30 days for the second  
year of your guarantee to become valid.  
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 Bosch Thermotechnology Ltd.  
The householder may be asked to prove the date of installation, that the boiler was  
correctly commissioned and, where appropriate, the first year’s service inspection  
has been carried out to the satisfaction of Bosch Thermotechnology Ltd., when  
requested. These should be part of the Benchmark Checklist.  
Any product or part returned for servicing under the guarantee must be  
accompanied by a claim stating the model, serial number & date of installation.  
Bosch Thermotechnology Ltd., 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 Commissioning and Servicing  
Instructions and User Instructions and Customer Care Guide.  
The boiler 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 and Eire.  
This guarantee does not affect your statutory rights.  
15  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
YOUR GUARANTEE  
GUARANTEE REGISTRATION  
You should complete and return the postpaid Guarantee  
Registration Card within 30 days of purchase.  
Returning the card will register you as the owner of your new  
Greenstar i junior boiler and will assist us in maintaining an  
effective and efficient customer service by establishing a  
reference and permanent record for your boiler.  
This does not affect your statutory rights.  
For your own record:  
Model  
Serial No.  
(See identity label inside boiler casing)  
Type / size  
Date of installation  
Name of Installer  
Telephone number of Installer  
Please ensure that the Benchmark Checklist has been  
completed by your installer or service engineer.  
16  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
GUARANTEE REGISTRATION  
NOTES  
WORCESTER BOSCH GREENSTAR 24i/28i Junior  
8 716 115 661 (05/2009)  
USER INSTRUCTIONS &  
CUSTOMER CARE GUIDE  
Dedicated to heating comfort  
Worcester, Bosch Group  
Cotswold Way, Warndon, Worcester WR4 9SW.  
Tel. 01905 754624 Fax. 01905 754619  
Worcester Bosch Group is a brand name of Bosch Thermotechnology Ltd.  
8 716 115 661 (05/2009)  

Acer Car Video System V233H User Manual
Aiphone Car Video System MY CU User Manual
Audiovox VBT100 User Manual
Blaupunkt RDM 169 US User Manual
Bosch Appliances GREENSTAR CDI C33 User Manual
Cateye Stadium Light HL MH310 User Manual
Clarion DXZ868RMP User Manual
Directed Video OHV901 User Manual
Hamilton Beach Coffee Urn User Manual
Jensen MS4200RS User Manual