Worcester GREENSTAR CDi CLASSIC SYSTEM User manual

UK/IE
USER INSTRUCTIONS
WALL HUNG RSF GAS FIRED CONDENSING SYSTEM BOILER
GREENSTAR CDi CLASSIC SYSTEM
6 720 812 179-00.1O
FOR CENTRAL HEATING SYSTEMS AND INDIRECT FED DOMESTIC HOT WATER
6 720 812 178 (2014/07)
The appliance is for use with:
Natural Gas or L.P.G. (CAT II 2H3P type C13 & C33)
Natural Gas:
30CDi GC number 41-406-37
35CDi GC number 41-406-39
L.P.G:
30CDi GC number 41-406-38
35CDi GC number 41-406-40

2
Preface
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
PREFACE
PLEASE READ THESE INSTRUCTIONS CAREFULLY
These instructions are applicable to the Worcester, Bosch
Group boiler model stated on the front cover only.
These instructions apply in the UK/IE only and must be followed
except for any statutory obligation.
After installation please leave this User instruction Manual,
Installation, Commissioning and Servicing Instructions and
completed Benchmark Checklist with the user.
DEDICATED TO HEATING COMFORT
Thank you for purchasing a Greenstar gas-fired condensing
regular 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 50 years. This heritage
means all our 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.
TABLE OF CONTENTS
1 Key to symbols and safety instructions . . . . . . . . . . . 3
1.1 Key to symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 General safety instructions . . . . . . . . . . . . . . . . . . 3
2 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Operating the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1 Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2 Switching the boiler ON/OFF . . . . . . . . . . . . . . . . 6
3.3 Setting the central heating temperature . . . . . . . 7
3.3.1Controlling the central heating . . . . . . . . . . . . . . . 7
3.4 Setting the hot water temperature
(only in conjunction with optional diverter valve)
8
3.5 Frost protection
(in conjunction with optional diverter valve) . . .9
3.6 Frost protection
(without optional diverter valve) . . . . . . . . . . . .9
3.7 eco mode (only in conjunction with optional diverter
valve) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3.8 Holiday setting (only in conjunction with optional
diverter valve) . . . . . . . . . . . . . . . . . . . . . . . . . .11
3.9 Fault condition . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 Fault finding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2 Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.3 Extreme cold weather . . . . . . . . . . . . . . . . . . . . . 15
5 General notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6 Fault or Breakdown . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7 Tips on energy saving . . . . . . . . . . . . . . . . . . . . . . . . . 17
8 Your guarantee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
9 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3
Key to symbols and safety instructions
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
1 KEY TO SYMBOLS AND SAFETY
INSTRUCTIONS
1.1 KEY TO SYMBOLS
WARNINGS
The following keywords are defined and can be used in this
document:
•NOTE indicates a situation that could result in damage to
property or equipment.
•CAUTION indicates a situation that could result in minor to
medium injury.
•WARNING indicates a situation that could result in severe
injury or death.
•DANGER indicates a situation that will result in severe
injury or death.
IMPORTANT INFORMATION
ADDITIONAL SYMBOLS
1.2 GENERAL SAFETY INSTRUCTIONS
These installation instructions are intended for gas fitters,
plumbers, heating engineers and electricians.
▶ Read any installation instructions (boiler, heating controls,
etc.) carefully before starting the installation.
▶ Observe the safety instructions and warnings.
▶ Observe national and regional regulations, technical rules
and guidelines.
▶ Record all work carried out.
IF YOU SMELL GAS
A gas leak could potentially cause an explosion. If you smell gas,
observe the following rules.
▶ Prevent flames or sparks:
– Do not smoke, use a lighter or strike matches.
– Do not operate any electrical switches or unplug any
equipment.
– Do not use the telephone or ring doorbells.
▶ Turn off the gas at the meter.
▶ Open windows and doors.
▶ Warn your neighbours and leave the building.
▶ Prevent anyone from entering the building.
▶ Well away from the building: call the National Gas
Emergency Service on 0800 111 999.
INTENDED USE
This boiler must only be used as a heat appliance in a sealed hot
water heating system for domestic purposes.
Any other use is considered inappropriate. Any damage that
results from such use is excluded from liability.
INSTALLATION, COMMISSIONING AND SERVICING
Installation, commissioning and servicing must only be carried
out by a competent, Gas Safe registered engineer.
▶ Carry out a gas tightness test after completing work on gas-
carrying components.
▶ Only use original spares.
ELECTRICAL WORK
Electrical work must only be carried out by a qualified
electrician.
▶ Before starting electrical work:
– Isolate the mains electrical supply and secure against
unintentional reconnection.
– Check for zero potential.
▶ Also observe connection diagrams of other system
components.
Warnings in this document are identified 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

4
General Information
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
HANDOVER TO THE USER
When handing over, instruct the user how to operate the
heating system and inform him about its operating conditions.
▶ Explain how to operate the heating system and draw the
user's attention to any safety-relevant action.
▶ Explain that modifications and repairs must only be carried
out by an authorised contractor.
▶ Advise the user to have the system serviced annually by a
competent, Gas Safe registered engineer.
▶ Leave the installation instructions with the completed
Benchmark Checklist (or a certificate confirming
compliance with IS 813, Eire only) and the operating
instructions with the user or at the gas meter.
2 GENERAL INFORMATION
SERVICING
• The boiler must be serviced regularly by a competent,
qualified person, such as a Worcester service engineer or
other Gas Safe registered engineer.
• Always use original spares, to help maintain the efficiency,
safety and reliability of the boiler and have the Service
Record completed in the Benchmark Checklist.
The completed Benchmark Checklist will be required in the
event of any guarantee work and may be required by the local
Building Control Inspector.
BENCHMARK STANDARD
The Benchmark initiative is a
code of practice to encourage the
correct installation,
commissioning and servicing of
domestic central heating boilers
and system equipment.
A “checklist” is dispatched with every boiler. This is a vital
document that needs to be completed by the installer at the
time of installation. It confirms that the boiler has been
installed and commissioned according to the manufacturer's
instructions.
The log book provides space for the recording of regular
servicing of the boiler/heating system and this can become a
valuable document when, for example, you wish to sell the
property. The log book will show a potential purchaser that the
heating system has received regular professional maintenance
and servicing during its lifetime.
The Benchmark initiative aims to:
• Raise standards among professional installers
• Build and maintain high safety standards in the industry
• Improve customer satisfaction levels
• Make a contribution to the nation's commitment to climate
change
Ensure that the service engineer completes the
Service Record in the Benchmark Checklist
after each service. The Benchmark Checklist
and service interval record can be found at the
rear of the Installation, Commissioning and
Servicing Instructions.

5
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3 OPERATING THE BOILER
3.1 CONTROLS
Fig. 1 Control panel
[1] ON/OFF button
[2] Position for optional programmer
[3] Display
[4] System pressure gauge
[5] Reset button
[6] Eco button
(only in conjunction with optional diverter valve)
[7] Holiday button
(only in conjunction with optional diverter valve)
[8] Domestic hot water temperature control
(only in conjunction with optional diverter valve)
[9] ON/OFF and fault indicator (Blue)
[10] Central heating temperature control
[11] Central heating boost button
[12] Service button
[13] Burner indicator (Green)
1 2 43
5
6
7
13
12
11
910 86 720 812 178-01.1O

6
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.2 SWITCHING THE BOILER ON/OFF
Fig. 2
Switching on
▶ Switch on the boiler by pressing the ON/OFF button.
The ON/OFF indicator light [1] shows blue.
Switching off
▶ Switch off the boiler by pressing the ON/OFF button.
The ON/OFF indicator light [1] goes out.
16 720 812 178-02.1O
The boiler runs for 15 minutes at minimum heating output to fill the condensate trap. The display [K] alternates
between and the central heating flow temperature.
This occurs every time the mains supply has been interrupted.

7
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.3 SETTING THE CENTRAL HEATING TEMPERATURE
▶ Turn the central heating temperature control to the desired
level, between approximately 35°C and 90°C.
When the burner is lit, the burner indicator light [1]
underneath the ON/OFF button shows green.
Fig. 3
3.3.1 CONTROLLING THE CENTRAL HEATING
Central heating systems must be controlled effectively using a
programmer or timer and a room thermostat.
▶ For further information on how to control your central
heating systemplease refer to the individual user guides for
the programmer or timer installed in your home.
min
min
6 720 812 178-03.1O
1
Position Central heating temperature
1approx. 35 °C
2approx. 43 °C
3approx. 50 °C
4approx. 60 °C
5approx. 67 °C
6approx. 75 °C
max approx. 90 °C
Table 2 Settings for the central heating temperature

8
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.4 SETTING THE HOT WATER TEMPERATURE
(ONLY IN CONJUNCTION WITH OPTIONAL DIVERTER VALVE)
Fig. 4
▶ Turn the domestic hot water temperature control [1] to the
desired level, between approximately 40°C and 60°C.
6 720 812 178-05.1O
2
3
Position Hot water temperature
min approx. 40 °C
eapprox. 50 °C
max approx. 60 °C
Table 3 Settings for the domestic hot water temperature

9
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.5 FROST PROTECTION
(IN CONJUNCTION WITH OPTIONAL DIVERTER VALVE)
Activating frost protection will turn off the boiler and prevent
heating of the central heating and domestic hot water cylinder.
If the temperature within the boiler drops to 5°C the boiler will
fire to avoid the possibility of freezing.
Fig. 5
To activate frost protection:
▶ Leave ON/OFF button [1] on.
▶ Turn the central heating temperature control to .
3.6 FROST PROTECTION
(WITHOUT OPTIONAL DIVERTER VALVE)
Frost protection is only guaranteed from the external room
temperature thermostat.
If remote pipework is likely to be subject to freezing conditions:
▶ Ensure the installer has fitted a frost thermostat in the area
to protect the pipework from freezing.
▶ Ensure the installer has added a suitable anti-freeze fluid to
the water in the central heating system.
6 720 812 178-04.1O
1

10
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.7 ECO MODE (ONLY IN CONJUNCTION WITH OPTIONAL DIVERTER VALVE)
Fig. 6
To deactivate eco mode:
▶ Press the eco button until it goes off.
When the eco button is not illuminated the hot water
cylinder has priority.
The hot water cylinder is first heated up and then the
appliance switches to central heating mode.
To re-activate eco mode:
▶ Press the eco button until it lights up.
When the eco button is illuminated the appliance switches
between central heating mode and cylinder charging
mode.
6 720 812 178-06.1O

11
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.8 HOLIDAY SETTING (ONLY IN CONJUNCTION WITH OPTIONAL DIVERTER VALVE)
Fig. 7
To activate holiday mode:
▶ Press the holiday button until it lights up.
When the holiday button lights up, central heating is
switched off.
Frost protection remains active.
To deactivate holiday mode:
▶ Press the holiday button until it goes off.
When the holiday button is not illuminated, the appliance
runs in normal mode.
6 720 812 178-07.1O

12
Operating the boiler
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
3.9 FAULT CONDITION
In the event of a fault occurring while the boiler is in operation
the reset button [2] and the fault indicator [3] will flash.
The display [1] will show an error code (for error codes see
table 5 on page 14).
Fig. 8
To reset the boiler:
▶ Press the reset button [2] for three seconds.
The reset button [2] and the fault indicator [3] will stop
flashing.
The boiler will function normally, dependent on
programmer and room thermostat settings.
6 720 812 178-08.1O
3
1
2
If the fault cannot be cleared by pressing the
reset button:
▶ Refer to the fault finding section on
page 13 of these user instructions.
▶ Call Worcester, Bosch Group, giving a
description of the fault and, if possible,
the fault code from the display.
Alternatively contact other Gas Safe
registered personnel for assistance.

13
Maintenance
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
4 MAINTENANCE
Your new Greenstar CDi Classic System gasfired appliance
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 service
contract, please tick the appropriate box on your warranty
registration card.
If your Greenstar CDi Classic System should fail to operate
correctly or requires servicing please contact the Worcester
Bosch Service Department (see back page cover for details).
Details of the boiler including the Gas Council number can be
found under the controls cover flap on the boiler.
4.1 FAULT FINDING
This table gives information on basic operating system
problems.
Problem Cause Remedy
EA fault code flashing on
display
No gas supply/low gas supply pressure ▶ Contact your gas supplier.
Condensate outlet blocked ▶ If it is safe to do so, check your condensate pipe
outlet for blockages, such as ice or foreign
objects.
Flue blocked ▶ If it is safe to do so, check your flue outlet for
damage or blockages.
Desired room temperature
is not reached
Thermostatic radiator valve(s) set too low ▶ Increase thermostatic radiator valve setting(s)
Temperature control for central heating flow
on boiler set too low
▶ Increase central heating flow temperature control
setting
Air trapped in heating system ▶ Bleed radiators and recharge heating system
Low temperature setting on the boiler
controls
▶ Increase settings on boiler controls
Desired room temperature
too high
Radiators are too hot ▶ Turn down thermostatic radiator valves/room
thermostat
▶Reducecentralheatingtemperature by turning
down the central heating control on boiler
Heating stays on too long Clock is incorrectly set ▶ Check setting and adjust
Hot water temperature
is too low
Temperature set too low ▶ Check settings and adjust
Hot water temperature
is too high
Temperature set too high ▶ Check settings and adjust
ON/OFF indicator is not
illuminated
Momentary power failure ▶ Disconnect boiler supply, wait a few seconds then
reconnect.
Table 4 Fault finding

14
Maintenance
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
4.2 ERROR CODES
When calling Worcester, Bosch Group, you may be asked for the error code. This Table is for you to help identify
the possible cause of the fault.
▶ Do not try to rectify any of the faults listed below by yourself.
▶ Contact British Gas or a competent, qualified engineer (Gas Safe registered personnel).
Error code Description
b1 Code plug not detected.
C6 Fan speed too low.
E9 Safety temp. limiter in CH flow has tripped.
EA Flame not detected.
If it safe to do so, check for:
• gas is on in the house
• frozen condensate pipe
• blocked flue outlet
F0 Internal error.
F7 Flame detected even though boiler switched off.
FA Flame detected after gas shut off.
Fd Reset button pressed by mistake.
Table 5 Error codes

15
General notes
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
4.3 EXTREME COLD WEATHER
In some instances where the condensate pipe work is run
externally or in an unheated area, such as a garage, the
condensate pipe work can be at risk of freezing, even if well
insulated.
The Greenstar CDi Classic contains a larger internal condesate
siphonic trap, but care should be taken in the location of a
condensate pipe.
A frozen/blocked condensate pipe will cause the boiler to shut
down.
If the condensate pipe has frozen:
▶ Locate the blockage.
It is likely that the pipe is frozen at the most exposed point
outside the building or where there is an obstruction to
flow.
This could be the open end of the pipe, at a bend or elbow,
or where there is a sag in the pipe in which condensate can
collect.
The location of the blockage should be identified as closely
as possible before taking further action.
▶Thawthefrozenpipe.
The pipe can be thawed by applying a hot water bottle, a
microwaveable heating pack (the sort used for muscular
aches and pains) or a cloth soaked in hot water to the
exterior of the pipe, close to the point of blockage.
Hot water, but not boiling, can also be poured onto the pipe
from a watering can or similar container.
▶ Once the pipe has been thawed the boiler must be reset,
press the reset button for five seconds and wait two to
three minutes for the boiler to restart.
▶ If the boiler does not restart, contact Worcester, Bosch
Group Appointments Team on:
0330 123 9559.
▶ Contact your installer in order to find a permanent solution
to the problem.
5 GENERAL NOTES
SEALED HAND CONDENSATE DRAIN
This is a condensing boiler and the flue 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 via a pipe to drain. This pipe must not be
blocked or altered in any way.
PLUMING AND CONDENSATE DRAIN
This is a condensing boiler and the flue 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 via a pipe to drain. This pipe must not be
blocked or altered in any way.
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.
This is usually more frequent during the summer months.
CLEARANCES
Your installer will have provided adequate space around the
boiler for safety and servicing access.
Fig. 9
* 600 mm service clearance required to a fixed surface
** 20 mm from removable door or panel
WARNING: Falling hazard!
Failure to follow this guidance may result in
personal injury.
▶ Only attempt to thaw a condense pipe that
is at ground level, and that is easily
accessible.
▶ Never attempt to thaw a condense pipe
that is at height.
CAUTION: Pipe damage
▶DO NOT use boiling water to thaw the
condensate pipe!

16
Fault or Breakdown
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
▶ Do not restrict this space with the addition of cupboards,
shelves etc. around or next to the boiler.
VENTILATION
This is a room sealed boiler and does not require any air for
combustion from inside the property. If a compartment is built
around the boiler after installation, then this must be carried
out as described in the Installation Manual.
SEALED HEATING SYSTEM
This appliance 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. 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 systemloses pressure it should be re-pressurised and the
cause of the fall investigated.
CENTRAL HEATING SYSTEMS
All radiators must be heated at an even rate. If the top of a
radiator is at a lower temperature than the bottom then it
should be bled by releasing air through the bleed screw at the
top of the radiator.
Ask your installer to show you how this is done.
This boiler is fitted to a sealed system. Should water leaks be
found or if excessive bleeding is required, then a service
engineer must be contacted to inspect the installation and
rectify any fault.
Only additives that are compatible with aluminium may be used
in the system. Any incompatible additive used will invalidate
the guarantee.
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 information on siting and
setting.
THERMOSTATIC RADIATOR VALVES
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 uncontrolled
and must be left open. The thermostatic radiator valves should
conform to the requirements of BS2767:10.
6FAULTORBREAKDOWN
This boiler is supported in the UK and Eire by Worcester, Bosch
Group.
Specialist Service Engineers are available to attend a
breakdown occurring on this boiler.
• No charge will be made for parts and/or labour providing:
– A boiler fault is found and the boiler is within the
guarantee period. Reasonable evidence of this must be
supplied on request. i.e. the Benchmark Checklist.
• A call-out charge will be made where:
– The boiler is outside the guarantee period.
– Evidence cannot be provided that the first year service
inspection has been carried out (i.e. an entry in the
Benchmark Checklist).
– Our Field Service Engineer finds no fault with the
boiler.
– The cause of breakdown is misuse or with other parts of
your plumbing/heating system, or with equipment not
supplied by Worcester, Bosch Group.
TECHNICAL SUPPORT
In the event of a boiler fault or breakdown please contact
Worcester, Bosch Group appointments team on:
0330 123 9559.
Your advisor 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 and bank
holidays) for priority breakdown situations (no hot water and/
or heating).
CAUTION: Risk of damage to the boiler.
▶ Do not operate the boiler if the flue
terminal is obstructed or damaged in any
way.
Invoices for attendance and repair work
carried out on this boiler by any third party will
not be accepted.
No boiler fault is found on over 30% of all
service calls.
In the case of a suspected fault, refer to the
fault finding section of this guide.

17
Tips on energy saving
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
7TIPSONENERGYSAVING
HEATING ECONOMICALLY
The boiler is designed to provide a 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 of heat
reduces. The technical term for this 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.
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.
CENTRAL HEATING SYSTEMS WITH ROOM THERMOSTATS
AND THERMOSTATIC RADIATOR VALVES
The central heating control on the boiler should be set to
maximum rated temperature ofthe central heating system. The
temperature of each room can be set individually (except room
with the room thermostat) using the thermostatic radiator
valves. If damaged, replace the plastic tops used to adjust the
thermostatic radiator valve. It is also advisable to manually
adjust all thermostatic radiator valves every 2-3 weeks to
prevent them sticking.
ROOM THERMOSTATS
Reducing the setting of the room thermostat by 1 °C can reduce
fuel consumption by up to 10 %.
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 200 mm thickness or more.
WINDOW FRAMES
Single glazed windows, particularly those with steel frames,
can loose a great deal of heat. Consideration should be given to
replacement with PVCu or wooden framed double glazing
units.
CURTAINS
Lined curtains, or heavier full length curtains can provide
excellent insulation. However, always ensure that the curtains
do not drape over radiators.
DRAUGHTS
Ensure that draughts around doors, windows, letterboxes and
keyholes etc. are reduced by using a suitable draught excluder.
RADIATORS
Often radiators are sited underneath a window. The
performance of the radiator will be affected if curtains are
allowed to drape over radiator or shelves are fitted above it.
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.

18
Your guarantee
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
8 YOUR GUARANTEE
This boiler has a guarantee against faulty materials or
workmanship for a period of two years from the date of
installation subject to the following terms and conditions:
• During the period of this guarantee any components of the
boiler 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 has been
carried out to the satisfaction of Bosch Thermotechnology
Ltd., when requested. These should be documented as a
part of the Benchmark Checklist.
• The boiler has been used only for the normal domestic
purposes for which it was designed.
This guarantee does not affect your statutory rights.
GUARANTEE REGISTRATION
Your Greenstar boiler carries a two year guarantee against
faulty material or manufacture subject to Terms and
Conditions.
To read the full Terms & Conditions please visit us on-line at
www.worcester-bosch.co.uk/guarantee. The Guarantee
Registration form is available on this same page and can be
completed and submitted electronically.
Alternatively please telephone one of our Guarantee
Registration advisors on 0330 123 9559.
Your statutory rights are not affected by the manufacturers
guarantee.
FOR YOUR OWN RECORD:
Please ensure that the Benchmark Checklist has been
completed by your installer or service engineer.
Model
Serial No.1)
Type/size
Date of installation
Name of Installer
Telephone number of Installer
Table 6
1) See boiler identification label on boiler fascia or Benchmark Checklist in the back of the Installation, Commissioning & Servicing
Instructions.

19
Glossary
GREENSTAR CDi CLASSIC SYSTEM – 6 720 812 178 (2014/07)
9GLOSSARY
PLUMING AND CONDENSATE DRAIN
This is a condensing boiler and the flue terminal will, at times
give out a plume of water vapour. This is quite normal.
The boiler produces condensate which is discharged regularly
by a syphon within the boiler via a plastic pipe to a drain. This
pipe must not be blocked or altered in any way.
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.
PUMP OVER RUN FUNCTION
After the boiler has finished a demand for central heating or hot
water, the pump may continue to run for a short while to
dissipate the heat from within the boiler.
ROOM THERMOSTAT / PROGRAMMER
A room thermostat / programmer must be fitted to control the
central heating. This controls the times and temperatures of
the central heating, preventing the boiler from firing
unnecessarily. Refer to the instructions supplied with the
thermostat and programmer for further information.
SEDBUK
Seasonal Efficiency of Domestic Boilers in the UK.
THERMOSTATIC RADIATOR VALVES
Thermostatic radiator valves must be fitted in sleeping
accommodation. It is recommended that this type of valve is
fitted to all but one of the radiators. The remaining radiator,
where the room thermostat is located, must be uncontrolled
and left open.

WORCESTER, BOSCH GROUP:
TECHNICAL SUPPORT: 0330 123 3366
APPOINTMENTS: 0330 123 9339
SPARES: 0330 123 9779
LITERATURE: 0330 123 9119
TRAINING: 0330 123 0166
SALES: 0330 123 9669
Worcester, Bosch Group
Cotswold Way, Warndon, Worcester WR4 9SW.
Tel. [phone]
Worcester, Bosch Group is a brand name of
Bosch Thermotechnology Ltd.
worcester-bosch.co.uk
6 720 812 178