Worcester GREENSTAR 24 User guide

INSTALLATION, COMMISSIONING AND SERVICING INSTRUCTIONS
WALL HUNG RSF GAS FIRED CONDENSING COMBINATION BOILER
GREENSTAR 24/28/30
6720643895-00.1Wo
FOR SEALED CENTRAL HEATING SYSTEMS AND MAINS FED DOMESTIC HOT WATER
6 720 811 922 (2014/07) UK
The appliance is for use with Natural Gas
(Cat I 2H type C13, C33 & C53)
Model GC Number
Natural Gas 24 kW 47-406-54
28 kW 47-406-56
30 kW 47-406-64

Contents
6 720 811 922 (2014/07)2
CONTENTS
1 Key to symbols and safety instructions . . . . . . . . . . . . . . . . . . . 3
1.1 Explanation of symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2 Appliance information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 Standard package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Boiler Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Appliance layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 Pre-Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.1 Cleaning primary systems . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2 Mains supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.1 Electrical supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.2 Gas supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.3 Water supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Water systems and pipe work . . . . . . . . . . . . . . . . . . . . . . 9
3.4 Condensate pipe work . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.1 Internal connections . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.2 External connections . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.5 Pressure relief pipe work . . . . . . . . . . . . . . . . . . . . . . . 12
3.6 Boiler location and clearances . . . . . . . . . . . . . . . . . . . 13
3.6.1 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6.2 Installation and servicing clearances - unventilated
compartments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6.3 Compartments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6.4 Bathrooms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.7 Flue options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.8 Flue terminal positions . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.9 Plume management terminal positions . . . . . . . . . . . . 17
4 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1 Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.2 Wall mounting template & flue opening . . . . . . . . . . . . 19
4.3 Pre-plumbing the boiler connections . . . . . . . . . . . . . . 20
4.4 Hanging the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.5 Flue installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.5.1 Measuring the flue (standard flue): . . . . . . . . . . . . . . . 22
4.5.2 Reducing the telescopic flue length: . . . . . . . . . . . . . . 22
4.5.3 Installing the telescopic flue: . . . . . . . . . . . . . . . . . . . . 22
4.5.4 Flue terminal plume re-direction: . . . . . . . . . . . . . . . . . 23
5 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2 Mains power connection . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2.1 New complete system installations . . . . . . . . . . . . . . . 24
5.2.2 Existing installations . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.3 Access to electrical connections . . . . . . . . . . . . . . . . . 24
5.3.1 Mounting optional plug-in controls . . . . . . . . . . . . . . . . 25
5.3.2 New complete system installations . . . . . . . . . . . . . . . 25
5.3.3 Existing installations . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5.4 Electrical wiring diagram . . . . . . . . . . . . . . . . . . . . . . . 27
6 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.1 Pre-commissioning checks . . . . . . . . . . . . . . . . . . . . . . . 28
6.2 Filling the system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.3 Water treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.4 Starting the appliance . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.5 Switching the appliance on/off . . . . . . . . . . . . . . . . . . . 30
6.6 Starting the central heating . . . . . . . . . . . . . . . . . . . . . . 30
6.7 Setting Low NOx heating output . . . . . . . . . . . . . . . . . . 30
6.8 Heating control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
6.9 CO and Combustion checks . . . . . . . . . . . . . . . . . . . . . . 31
6.10 Finishing commissioning . . . . . . . . . . . . . . . . . . . . . . . . 31
6.11 Setting the DHW temperature . . . . . . . . . . . . . . . . . . . . 32
6.12 Summer mode
(central heating off, DHW only) . . . . . . . . . . . . . . . . . . . 32
6.13 Frost protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.14 Button lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
7 Setting the control panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
7.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
7.2 Service functions overview . . . . . . . . . . . . . . . . . . . . . . 34
7.2.1 Service level 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
7.2.2 Service level 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
7.3 Description of service functions . . . . . . . . . . . . . . . . . . 35
7.3.1 Service level 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
7.3.2 Service level 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
8 Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
8.1 Checking the gas supply pressure . . . . . . . . . . . . . . . . . 38
8.2 Check flue integrity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
8.3 Checking flue system for tightness . . . . . . . . . . . . . . . . 38
8.4 Measuring CO content of flue gas . . . . . . . . . . . . . . . . . 39
8.5 Setting gas/air ratio (CO2) . . . . . . . . . . . . . . . . . . . . . . . 39
8.6 Fan pressure test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9 Environmental protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
10 Inspection/Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
10.1 Description of various maintenance operations . . . . . . 41
10.1.1 Draining the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
10.1.2 Checking heat exchanger, burner and electrodes . . . . 41
10.1.3 Filter in cold water pipe . . . . . . . . . . . . . . . . . . . . . . . . . 43
10.1.4 Plate heat exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
10.1.5 Gas valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
10.1.6 3-way diverter valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
10.1.7 Replacing the diverter valve motor . . . . . . . . . . . . . . . . 44
10.1.8 Pump and return manifold . . . . . . . . . . . . . . . . . . . . . . . 44
10.1.9 Cleaning condensate trap . . . . . . . . . . . . . . . . . . . . . . . . 45
10.1.10Diaphragm in mixer unit . . . . . . . . . . . . . . . . . . . . . . . . . 45
10.1.11Checking the expansion vessel . . . . . . . . . . . . . . . . . . . 45
10.1.12Changing the expansion vessel . . . . . . . . . . . . . . . . . . . 45
10.1.13Setting the heating system pressure . . . . . . . . . . . . . . . 45
10.1.14Checking wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
10.1.15Cleaning of other components . . . . . . . . . . . . . . . . . . . . 46
10.2 Short parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Key to symbols and safety instructions
6 720 811 922 (2014/07) 3
11 Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
12 Fault finding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
12.1 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
12.2 Faults that are displayed . . . . . . . . . . . . . . . . . . . . . . . . 48
12.3 Faults that are not displayed . . . . . . . . . . . . . . . . . . . . . 49
12.4 Sensor values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
12.4.1 Flow temperature sensor . . . . . . . . . . . . . . . . . . . . . . . 49
12.4.2 DHW temperature sensor . . . . . . . . . . . . . . . . . . . . . . . 49
12.5 Code plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1 KEY TO SYMBOLS AND SAFETY INSTRUCTIONS
1.1 EXPLANATION OF SYMBOLS
WARNING SYMBOLS
Signal words indicate the seriousness of the hazard in terms of the
consequences of not following the safety instructions.
•NOTICE indicates possible damage to property or equipment, but
where there is no risk of injury.
•CAUTION indicates possible injury.
•WARNING indicates possible severe injury.
•DANGER indicates possible risk to life.
IMPORTANT INFORMATION
ADDITIONAL SYMBOLS
SYMBOLS USED IN THIS MANUAL
PLEASE READ THESE INSTRUCTIONS CAREFULLY BEFORE
STARTING INSTALLATION.
Safety instructions in this document are framed and
identified by a warning triangle which is printed on a
grey background.
Notes contain important information in cases where
there is no risk of personal injury or material losses and
are identified by the symbol shown on the left. They are
bordered by horizontal lines above and below the text.
Symbol Meaning
1. a numbered step in an action sequence
▶ a step in an action sequence
a reference number to identify or refer to a part or item
• a list entry
– a list entry (second level)
Table 1 Symbols
Domestic Hot Water
Central Heating
Hot Water Storage Cylinder
Domestic Cold Water Supply
Electrical Supply
Gas Supply
Table 2 Commonly used symbols
1
These instructions are applicable to the Worcester appliance model(s)
stated on the front cover of this manual only and must not be used with
any other make or model of appliance.
These instructions apply in the UK and Ireland only and must be
followed except for any statutory obligations.
This appliance must be installed by a GAS SAFE registered,
competent person. Failure to install correctly could lead to
prosecution.
If you are in any doubt, contact the Worcester Technical helpline
(0844 892 3366).
Please leave these instructions with the completed BENCHMARK
CHECKLIST, (or a certificate confirming compliance with IS 813, Eire
only) and the user manual with the owner or at the gas meter after
installation or servicing.
Distance learning and training courses are available from Worcester.
The BENCHMARK CHECKLIST can be found in the back of this
Installation manual.
Table 3
ØDiameter
NG Natural Gas
LPG Liquid Petroleum Gas
CH Central Heating
DHW Domestic Hot Water
DCW Domestic Cold Water
PRV Pressure Relief Valve
NTC Negative Temperature Coefficient (sensor)
IP Ingress Protection
RCD Residual Current Device
TRV Thermostatic Radiator Valve
ECV Emergency Control Valve
WRAS Water Regulations Advisory Scheme
SEDBUK Seasonal Efficiency of Domestic Boilers in the United
Kingdom
Table 4 Abbreviations used in this manual

Key to symbols and safety instructions
6 720 811 922 (2014/07)4
1.2 SAFETY PRECAUTIONS
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.
▶ Leave the building and warn your neighbours.
▶ Prevent anyone from entering the building.
▶ Stay well away from the building: call the National Gas Emergency
Service on 0800 111 999.
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.
Benchmark places
responsibilities on both
manufacturers and
installers. The purpose is to
ensure that customers are provided with the correct equipment for their
needs, that it is installed, commissioned and serviced in accordance
with the manufacturer's instructions by competent persons and that it
meets the requirements of the appropriate Building Regulations. The
Benchmark Checklist can be used to demonstrate compliance with
Building Regulations and should be provided to the customer for future
reference.
The guarantee of this product is dependant on the Benchmark checklist
being completed and the actions undertaken.
Installers are required to carry out installation, commissioning and
servicing work in accordance with the Benchmark Code of Practice
which is available from the Heating and Hotwater Industry Council who
manage and promote the scheme.
Visit centralheating.co.uk for more information.
HEALTH AND SAFETY
The appliance contains no asbestos and no substances have been used
in the construction process that contravene the COSHH Regulations
(Control of Substances Hazardous to Health Regulations 1988).
COMBUSTION AND CORROSIVE MATERIALS
Do not store or use any combustible materials (paper, thinners, paints
etc.) inside or within the vicinity of the appliance.
Chemically aggressive substances can corrode the appliance and
invalidate any guarantee.
FITTING AND MODIFICATIONS
Fitting the appliance and any controls to the appliance may only be
carried out by a competent engineer in accordance with the current Gas
Safety (Installation and Use) Regulations.
Flue systems must not be modified in any way other than as described in
the fitting instructions. Any misuse or unauthorised modifications to the
appliance, flue or associated components and systems could invalidate
the guarantee. The manufacturer accepts no liability arising from any
such actions, excluding statutory rights.
SERVICING
Advise the user to have the system serviced annually by a competent,
qualified Gas Safe registered engineer. Approved spares must be used
to help maintain the economy, safety and reliability of the appliance.
IMPORTANT
The service engineer must complete the Service Record on the
Benchmark Checklist after each service.
INSTALLATION REGULATIONS
Current Gas Safety (Installation & Use) Regulations:
All gas appliances must be installed by a competent person in
accordance with the above regulations.
Failure to install appliances correctly could lead to prosecution.
The appliance must be installed in accordance with, and comply to, the
current: Gas Safety Regulations, IEE Regulations, Building Regulations,
Building Standards (Scotland) (Consolidation), Building Regulations
(Northern Ireland), local water by-laws, Health & Safety Document 635
(The Electricity at Work Regulations 1989) and any other local
requirements.
BUILDING REGULATIONS PART L 1A 2010
If the installation is ina new build property or is a first time installation in
an existing property, heating systems must conform to current building
regulations Part L1a.
All new heating systems in dwellings must have at least two heating
zones. Each of these zones will be operated separately by both time and
temperature controls.
The exception to this are single storey, open plan dwellings where the
living area is more than 70% of the total useable floor area. Then this
type of dwelling can be controlled as one zone.
All radiators must have TRVs fitted, where reasonable, in all rooms
except bathrooms and rooms with thermostats.
BUILDING REGULATIONS PART L 1B 2010 - BOILER REPLACEMENT
For boiler replacement on an existing system, it is not necessary to zone
the system, compliance with the zone requirements can be achieved by
a single room thermostat or programmable room thermostat.
BRITISH STANDARDS
Where no specific instruction is given, reference should be made to the
relevant British Standard codes of Practice.
BS7074:1 Code of practice for domestic and hot water supply
BS6891 Installation of low pressure gas pipe work up to 28mm (R1)
BS5546 Installation of gas hot water supplies for domestic purposes
EN12828 Central heating for domestic premises
BS5440:1 Flues and ventilation for gas appliances of rated heating not
exceeding 70kW (net) : Flues
BS5440:2 Flues and ventilation for gas appliances of rated heating not
exceeding 70kW (net) :
Air Supply
BS7593 Treatment of water in domestic hot water central heating
systems
BS6798 Installation of gas fired boilers of rated input up to 70kW (net)
Irish Standards
The relevant Irish standards should be followed, including:
• ECTI National rules for electrical installations
• IS 813:2002 for Domestic Gas Installations.
Timber framed building:
Where the boiler is to be fitted to a timber framed building the guidelines
laid down in BS5440: Part 1 and IGE "Gas Installations in Timber Frame
Buildings” should be adhered to.
Potable water:
All seals, joints and compounds (including flux and solder) and
components used as part of the secondary domestic water system must
be approved by WRAS.

Appliance information
6 720 811 922 (2014/07) 5
CH Water:
Artificially softened water must not be used to fill the central heating
system.
2 APPLIANCE INFORMATION
2.1 STANDARD PACKAGE
Fig. 1
2.2 BOILER FEATURES
• Gas condensing boiler
• Pump anti-seize protection
• Compatible with all Worcester standard and intelligent controls
• Mains electrical cable pre-wired to control board
• Built-in fault-finding diagnostics
• Automatic ignition
• Modulating output control
• No minimum water circulation rate required
• Suitable for underfloor heating
• Condensfit II flue systems 60/100 and 80/125mm allows plume re-
direction as standard and ability to attach plume management kits
• Variable speed fan
• Premix burner
• Three-speed heating circulating pump with automatic air vent
• Pressure relief valve, pressure gauge, expansion vessel
• Flue gas temperature limiter (120 °C)
• Motorised 3-way diverter valve delivering DHW as a priority
• Plate heat exchanger
• Condensate trap
• Top wall hanging plate
• Isolating valves hanging bracket for pre-plumbing
Standard package contents:
1 Gas Combi boiler
Bottom Tray
2 Literature pack:
- Installation instructions
- User guide
- Wall mounting template
- PRV installer connection
- Condensate adapter
3 Hardware pack:
- Compression fittings
- Fibre washers
5 Top wall hanging bracket
6 Fascia flap
Top Tray
4 Isolating valve bracket
Table 5
6720800945-01.1Wo
1
3
2
4
5
6

Appliance information
6 720 811 922 (2014/07)6
2.3 TECHNICAL DATA
Greenstar 24, 28, and 30 UNIT 24 28 30
Domestic Hot Water
Minimum heat input kW 7.5 7.5 7.3
Maximum rated heat output kW 24 28 29.6
Maximum rated heat input (net) kW 24.6 28 30
Maximum mains inlet pressure (standing pressure) bar 10 10 10
Minimum mains inlet pressure (working) for max. flow bar 1.5 1.5 1.5
Minimum mains inlet pressure (working) for operation bar 0.2 0.2 0.3
Domestic hot water temp. range °C 40-60 40-60 40-60
Domestic Hot water specific rate - 30 °C rise l/min 11.4 13.4 14.0
Max. Domestic Hot Water flow rate - 40 °C rise 15% l/min 8.6 10.0 10.5
Gas flow rate - Max. 10 minutes from lighting
Natural Gas G20 m³/h 2.5 2.8 3.0
Central Heating
Max. rated heat output 40/30°C kW 21.8 21.8 21.8
Max. rated heat output 50/30°C kW 21.6 21.6 21.6
Max. rated heat output 80/60°C kW 20.3 20.3 20.3
Max. rated heat output with low NOx kW 14.1 14.1 14.1
Maximum flow temperature °C 88 88 88
Max. permissible operating pressure bar 2.5 2.5 2.5
Available pump head at 20°C system temperature rise m 222
Flue
Flue gas temperature 80/60°C, rated/min. load °C 85/61 94/61 94/61
Flue gas temperature 40/30°C, rated/min. load °C 60/32 60/32 60/32
CO2level at max. rated heat output (after 30 minutes) % 9.6 9.6 9.8
CO2level at min. rated heat output (after 30 minutes) % 8.7 8.7 8.8
Standard NOx class & rating mg/kWh 5 42.0 42.0 42.0
Low NOx class & rating mg/kWh 5 37.8 37.8 37.8
Condensate
Maximum condensate rate l/h 1.7 1.7 1.7
pH value, approx. 4.8 4.8 4.8
Electrical
Electrical power supply voltage a.c. V 230 230 230
Frequency Hz 50 50 50
Max. power consumption - running W 125 125 130
Maximum power consumption - stand-by W 444
General data
Appliance protection rating IP IP X4D IP X4D IP X4D
Appliance protection rating with FW100 or FR110 module fitted IP IP20 IP20 IP20
Permissible ambient temperatures °C 0 - 50 0 - 50 0 - 50
Nominal capacity of appliance litre 333
Total boiler weight kg 48.6 48.6 48.6
Lift weight kg 45.6 45.6 45.6
SEDBUK 2005 Band A 90.0% 90.0% 90.0%
SEDBUK 2009 Annual 88.6% 88.6% 88.6%
Table 6

Appliance information
6 720 811 922 (2014/07) 7
2.4 APPLIANCE LAYOUT
Fig. 2 Main boiler components
[1] Control panel
[2] ON/OFF button
[3] Burner ON indicator light (green)
[4] Service button
[5] Performance test button
[6] CH temperature control
[7] Mains ON/OFF indicator / diagnostic light (blue)
[8] Position for optional plug-in control
[9] DHW temperature control
[10] Key lock
[11] eco button
[12] Fault reset button
[13] System pressure gauge
[14] Display
[15] CH flow pipe to isolating valve
[16] DHW temperature sensor
[17] DHW plate heat exchanger
[18] 3-way diverter valve
[19] Condensate trap
[20] Diverter valve actuator (stepper motor)
[21 ] Gas valve
[22] Inlet pressure test point
[23] CH flow
[24] Flow temperature sensor (NTC)
[25] Air pressure switch (30 kW only)
[26] Expansion vessel
[27] Flue connector
[28] Fan
[29] Combustion air inlet
[30] Maximum safety sensor (NTC)
[31] Electrode assembly
[32] Fan pressure test point
[33] Flue overheat thermostat
[34] Sump assembly
[35] Auto air vent
[36] Pump
[37] Drain point
[38] CH return connection to isolating valve
[39] DCW in connection to isolating valve
[40] Gas pipe from isolating valve
[41] DHW outlet pipe
[42] Safety valve (heating circuit)
27
15
16
1
2
3
4
5
11
12
13
14
689
7
10
6 720 811 922-01.1O
24
17
23
22
20
19
18
21
25
26 28
29
30
31
32
33
34
35
37
39
40
41
42
36
38

Pre-Installation
6 720 811 922 (2014/07)8
3PRE-INSTALLATION
3.1 CLEANING PRIMARY SYSTEMS
BEFORE CLEANING THE SYSTEM:
▶ Ensure that the system and pipe work is in good working order.
▶Where possible keep the existing boiler/circulating pump in
place when flushing the system.
FOLLOW THE GUIDANCE OF BS7593:
Treatment of water in domestic hot water central heating and also the
flushing guidelines below.
FLUSHING THE SYSTEM
▶ Fill the system with cold water and check for leaks.
▶ Open all drain cocks and drain the system.
▶ Close drain cocks and add a suitable flushing agent compatible with
aluminium at the correct strength for the system conditions in
accordance with the manufacturer‘s instructions.
The pH value of the system water must be less than 8 or the
appliance guarantee will be invalidated.
▶ Circulate the flushing agent before the boiler is fired up.
▶ Run the boiler/system at normal operating temperature as directed
by the manufacturer of the flushing agent.
▶ Drain and thoroughly flush the system to remove the flushing agent
and debris.
▶ It may be necessary to use a power flushing machine to aid the
cleansing procedure in some circumstances.
▶ Close the drain cocks and refill with fresh water and a suitable
inhibitor.
▶ Vent any air from the boiler and system.
INHIBITOR
Add a suitable inhibitor or combined inhibitor/anti-freeze, if the system
is exposed to freezing conditions, to the heating system in accordance
with the DWTA code of practice and manufacturer‘s guidelines.
WATER TREATMENT PRODUCTS
Suitable water treatment products can be obtain from the following
manufacturers:
ARTIFICIALLY SOFTENED WATER
It is possible to have an Ion exchange water softener fitted to the cold
water system of the property. However, the boiler requires an untreated
cold water connection taken from the mains supply, before the water
softener, to the primary water filling point of the heating system.
Alternatively there are water softening/treatment devices that do not
adjust or alter the pH levels of the water. With these devices it may not
benecessary to provide an untreatedwater by-pass to theprimarywater
filling point of the heat system.
3.2 MAINS SUPPLY
3.2.1 ELECTRICAL SUPPLY
• Supply: 230V - 50 Hz, 130 Watts
• Cable: PVC insulated H05VVF 3G1 (3 x 1mm2 ) temperature rated to
90 °C.
• External 3A fuse to BS1362.
• The boiler must be earthed.
• This boiler must not be connected to a 3 phase supply.
• IPX4D.
• Wiring must comply with the latest edition of BS 7671 (IEE wiring
regulations).
3.2.2 GAS SUPPLY
• Boilers using Natural Gas (NG) must be connected to a governed
meter.
• Installation and connection of the gas supply to the boiler must be in
accordance with BS6891.
• Under no circumstance should the size of the gas supply pipe be less
than 22 mm.
• The meter or regulator and pipe work to the meter must be checked,
preferably by the gas supplier.
This is to ensure that the equipment is in good working order and can
meet the gas flow and pressure requirements, in addition to the
demand from any other appliance being served.
3.2.3 WATER SUPPLY
WATER MAINS PRESSURE:
• Minimum mains water pressure for maximum performance: 1.5 bar.
• Maximum mains fed water pressure 10 bar.
If necessary fit a pressure reducing valve.
CAUTION:
▶ ISOLATE THE MAINS SUPPLIES BEFORE STARTING
ANY WORK AND OBSERVE ALL RELEVANT SAFETY
PRECAUTIONS.
NOTICE:
▶ All the following pre-installation sections must be
read and requirements met before starting the boiler
or flue installations.
NOTICE:
▶ Debris from the system can damage the boiler and
reduce efficiency.
Failure to comply with the guidelines for the use of
water treatment with the appliance will invalidate the
appliance guarantee and contravene the Building
Regulations.
▶Itisrecommendedthatyou fit a primary water
cleanser to the system. Worcester recommends a
filter that will help remove both magnetite and non-
magnetic debris.
NOTICE: Artificially softened water must not be used to
fill the central heating system.
WARNING: Sealing agents
▶ Normally the addition of sealing agents to the system
water is not permitted as this can cause problems
with deposits left in the heat exchanger.
▶ In cases where all attempts to find a micro leak have
failed, Worcester, Bosch Group supports the use of
Fernox F4 leak sealer.
FERNOX 0870 601 5000 or www.fernox.com
SENTINEL 0800 389 4670 or www.sentinel-solutions.net
Table 7
NOTICE: This is reduced to IP20 if the following
mechanical timers are fitted;
7 716 192 036 or 7 716 192 037
or FW100 7 716 192 067

Pre-Installation
6 720 811 922 (2014/07) 9
• Where the mains water supply has a non-return,
back flow prevention valve fitted, a mini expansion vessel (1) should
be connected to the mains water inlet pipe (2) between the non-
return valve (3) and the boiler (4) as shown below.
Fig. 3
[1] Mini expansion vessel - part no. 7 716 192 105
[2] Mains water inlet pipe
[3] Non return valve
[4] Boiler
USE IN HARD WATER AREAS:
Normally there is no need for water treatment to prevent scale formation
as the maximum temperature of the DHW heat exchanger is limited by
the electronic control.
In areas where temporary water hardness exceeds 200 ppm,
consideration may need to be given to the fitting of a scale prevention
device. In such circumstances, the advice of the local water authority
should be sought.
3.3 WATER SYSTEMS AND PIPE WORK
PLASTIC PIPE WORK:
• Any plastic pipe work must have a polymeric barrier with 600mm
(minimum) length of copper pipe before being connected to the
boiler.
• Plastic pipe work used for underfloor heating must be correctly
controlled with a thermostatic blending valve limiting the
temperature of the circuits to approximately 50°C.
PRIMARY SYSTEMS CONNECTIONS/VALVES:
• All system connections, taps and mixing valves must be capable of
sustaining a pressure up to 3 bar.
• Radiator valves should conform to BS2767:10.
• All other valves should conform to BS1010.
• Thermostatic radiator valves (TRV’s) must be fitted to all rooms
except bathrooms and the room in which the room thermostat is
fitted.
• A drain cock is required at the lowest point(s) in the system.
• An air vent is required at the high point(s) in the system.
SHOWERS/BIDETS:
• If a shower head can be immersed in water or comes closer than
25mm from the top edge of a bath or shower tray spill over level then
an anti-syphon device must be fitted to the shower hose.
• Bidets with direct hot and cold mains water can be used (with the
approval of the local water authority) and must be the over rim
flushingtype with shrouded outlets to prevent thefitting of handheld
sprays.
SEALED PRIMARY SYSTEM:
• The CH sealed system must be filled using a WRAS approved filling
loop or comply with figure 4 for system fill.
• Where the system volume is more than 100 litres or exceeds 2.65
bar at maximum heating temperature, an extra expansion vessel (2)
must be fitted as close as possible to the appliance in the central
heating return.
• Pressurise the extra expansion vessel (2) to the same figure as the
expansion vessel built into the appliance.
•Do not use galvanised pipes or radiators.
SYSTEM FILL
Fig. 4 System fill
TYPICAL SEALED SYSTEM
Fig. 5 Sealed system
NOTICE: Non return, back flow prevention devices
(including those associated with water meters) fitted to
the mains water supply can cause a pressure build up
which could damage the boiler and other household
appliances.
The boiler is equipped with an internal by-pass.
The internal bypass is not intended to be a substitute for
an external system bypass.
An external automatic bypass should be used if the
system flow can be significantly adjusted or stopped by
zone valves and thermostatic radiator valves (TRV).
1
4
32
6720643895-04.1Wo
NOTICE: ARTIFICIALLY SOFTENED WATER MUST NOT
BE USED TO FILL THE CENTRAL HEATING SYSTEM
CV = Check Valve
SV = Stop Valve
SV SV
Test point
Temporary hose
Hose union CV
CV
Heating
return
Mains
supply
6720643895-05.1Wo
44
1
2
3
5 5
55
6720643895-06.1Wo

Pre-Installation
6 720 811 922 (2014/07)10
Fig. 6 Sealed system with zone valves
3.4 CONDENSATE PIPE WORK
3.4.1 INTERNAL CONNECTIONS
In order to minimise risk of freezing during prolonged cold spells, the
following methods of installing condensate drainage pipe should be
adopted, in order of priority.
Wherever possible, the condensate drainage pipe should be routed and
terminated so that the condensate drains away from the boiler under
gravity to a suitable internal foul water discharge point such as an
internal soil and vent stack. A suitable permanent connection to the foul
waste pipe should be used.
Fig. 7 Disposal to soil vent stack
Alternatively if the first option is not possible an internal kitchen or
bathroom waste pipe, washing machine waste pipe etc. can be used.
Ensure that the condensate drain pipe is connected “down stream” of
the waste trap.
Fig. 8 Disposal to a waste pipe
CONDENSATE PUMP
Where “gravity discharge” to an internal termination is not physically
possible, or where very long internal runs would be required to reach a
suitable discharge point, condensate should be removed using a
proprietary condensate pump, of a specification recommended by the
boiler or condensate pump manufacturer.
The pump outlet pipe should discharge to a suitable internal foul water
discharge point such as an internal soil and vent stack, internal kitchen
or bathroom waste pipe, washing machine waste pipe etc. A suitable
permanent connection to the foul waste pipe should be used.
1 Appliance expansion vessel - CH
2 Extra expansion vessel - CH return
3 Pressure relief discharge
4 Drain cock
5Radiators
6 Zone valves
Table 8 Key to figs. 3 5 and 6 4
NOTICE:
▶ Where a new or replacement boiler is being installed,
access to an internal “gravitydischarge” pointshould
be one of the factors considered in determining
boiler location.
▶ The condensate pipe must be nominally
22mm Ø plastic pipe.
▶ The condensate pipe work must fall at least 52mm
per metre towards the outlet and should take the
shortest practicable route.
▶ Ensure there are no blockages in the pipe run.
Key to condensate illustrations (Fig. 7 – Fig. 13)
1 Condensate discharge from boiler
2 Soil and vent stack
3 Minimum 450mm and up to three storeys
4 Visible air break at plug hole
5 Sink or basin with integrated overflow
6 75mm sink waste trap
7 Condensate pump
8 PVCu strap on fitting
9 100mm Ø minimum plastic pipe
10 Drainage holes
11 Limestone chippings
12 Bottom of sealed tube
13 Insulate and increase pipe size
14 Pipe work transition
15 External air break
16 Air gap
17 External rain water pipe into foul water
18 43mm 90° male/female bend
* Condensate trap of 75mm already incorporated into the boiler
Table 9
4
6
4
2
3
5 5
55
M
M
6720646608-04.1Wo
1
2
22mm Ø
1
3
6720644744-06.2Wo
*
100mm
75mm
min.
4
5
6
1
22mm Ø
6720644744-07.2Wo
*

Pre-Installation
6 720 811 922 (2014/07) 11
Fig. 9 Condensate pump disposal
3.4.2 EXTERNAL CONNECTIONS
If no other discharge method is possible then the use of an externally run
condensate drainage pipe terminating at a suitable foul water discharge
point, or purpose-designed soak away, may be considered. If this
method is chosen then the following measures should be adopted:
▶ The external run be kept as short as possible and not exceed three
metres.
▶ The pipe should be run internally as far as possible before going
externally and the pipe diameter should be increased to 32mm
before it passes through the wall to the exterior. The pipe should be
insulated using suitable waterproof and weather resistant insulation.
▶ The external pipe should take the shortest and leastexposed route to
the discharge point, and should "fall" as steeply as possible away
from the boiler, with no horizontal runs in which condensate might
stand.
▶ The use of fittings, elbows etc. should be kept to a minimum and any
internal “burrs” on cut pipe work should be removed so that the
internal pipe section is as smooth as possible.
FITTING AN EXTERNAL AIR BREAK
• Refer to figure 10 when a rain water down pipe is used to dispose of
condensate.
• An air break must be installed in the 43mm pipe work, between the
boiler condensate outlet and the drainpipe, outside the property, to
avoid flooding during adverse weather conditions.
Fig. 10 Disposal into a rainwater down pipe
Where the pipe terminates over an open drain or gully, the pipe should
terminate below the grating level, but above water level, in order to
minimise “wind chill” at the open end.
The use of a drain cover (such as those used to prevent blockage by
leaves) may offer further protection from wind chill.
Pipe drainage will be improved if the end is cut at 45° as opposed to a
straight cut.
Fig. 11 External disposal
CONDENSATE SOAK AWAY
• The condensate drainage pipe may be run above or below the ground
to the soak away. The examples shown on this page run above
ground.
• The soak away must use a 100mm Ø plastic tube with two rows of
three 12mm holes on 25mm centres and 50mm from the bottom of
the tube. The holes must face away from the house.
• The tube must be surrounded by at least 100mm of limestone
chippings to a depth of 400mm.
NOTICE: Freezing conditions
▶ Pipe work length should be kept to a minimum and
the route as vertical as possible.
▶ Weather proof insulation must be used.
NOTICE: Condensate waste
▶ Care should be taken when siting a soak-away to
avoid obstructing existing services.
75mm
min.
4
7
5
6
1
22mm Ø
6720644744-08.2Wo
*
Condensate drainage pipe can be run above or below
ground.
Minimumholesizeforthecondensatesoakawaymustbe
400mm deep by 300mmØ .
18 8
13
14
17
15
16
1
6720644744-09.2Wo
*
25mm min.
14
13
1
6720644744-10.2Wo
*

Pre-Installation
6 720 811 922 (2014/07)12
In situations where there are likely to be extremes of temperature or
exposure, the use of a proprietary trace-heatingsystem for external pipe
work, incorporating an external frost thermostat, should be considered.
If such a system is used, the requirement to use 32mm pipe does not
apply. However, all other guidance above and the instructions for the
trace heating system, should be closely followed.
Fig. 12 Soak away
Fig. 13 Condensate pump to external disposal
3.5 PRESSURE RELIEF PIPE WORK
• The pressure relief drain pipe (1) from the boiler should be at least
15mm diameter copper pipe and run downwards, away from any
electrical equipment or other hazard, preferably to an external drain
or soak away.
• The pressure relief drain pipe (1) should be finished with a partial
bend, near the outlet to face the external wall (as shown) to help
prevent freezing.
Fig. 14 Pressure relief pipe work
NOTICE: Unheated internal areas.
▶ Internal pipe runs in unheated areas such as lofts,
basements and garages should be treated as
external runs.
NOTICE:
▶ The pressure relief valve is a safety device for the
boiler and if activated may discharge boiling water or
steam through the relief valve drain pipe.
▶ Care should be taken when siting the outlet pipe so
that it does not cause an obstruction or discharge
above a window, entrance or other public access
where it could cause a hazard.
13
14
10
500mm min.
25mm min.
400mm
min.
1
12
11
9
6720644744-11.2Wo
9
10
*
25mm min.
14 13
1
7
6720644744-12.2Wo
*
2Outsidewall
1,3 Drain pipe
4Externaldrain
Table 10 Key to fig 7
6720643895-08.1Wo
1
2
3
4

Pre-Installation
6 720 811 922 (2014/07) 13
3.6 BOILER LOCATION AND CLEARANCES
3.6.1 INSTALLATION
This boiler is only suitable for installing internally within a property at a
suitable location onto a fixed, rigid surface at least the same size as the
boiler and capable of supporting the boiler weight.
3.6.2 INSTALLATION AND SERVICING CLEARANCES -
UNVENTILATED COMPARTMENTS
Fig. 15 Compartment clearances
[*] Minimum clearance to removable door
[**] Minimum clearance required for servicing
[***] Minimum clearance required to remove expansion vessel with
boiler mounted with left or right flue exit
3.6.3 COMPARTMENTS
Follow the requirements of BS6798 and BS5440 Part 2 and note:
• Minimum clearances must be maintained.
• An access door is required to install, service and maintain the boiler
and any ancillary equipment.
• If fitting the boiler into an airing cupboard use a non-combustible
material to separate the boiler from the airing space.
The material can be perforated up to a maximum hole size of 13mm.
3.6.4 BATHROOMS
A boiler fitted with a mechanical timer or RF mechanical timer (receiver)
or FW100 controller may only be installed outside the shaded area.
A boiler with any other timer fitted (or blanking panel) can also be
installed in zone 2.
Additional RCD (Residual Current Device) protection may be required.
Consult the latest version of BS7671 (IEE wiring regulations).
Fig. 16 Bathroom installations
3.7 FLUE OPTIONS
NOTICE:
No surface protection is required against heat transfer
from the boiler
min.
10
min.
10
400
15
840
850
6720800945-02.1Wo
370
200**
170 (60/100 flue)**
210 (80/125 flue)**
400 ***
600**
20*
218
125
80
CAUTION: Non accessible flue systems:
▶ Where a flue system is not going to be accessible,
provision must be made for service and inspection.
▶ Voids containing concealed flues must have at least
one inspection hatch no less than 300mm square.
▶ Flue joints within the void must not be more than 1.5
metres from the edge of the inspection hatch.
▶ Inspection hatches should be located at changes of
direction.
▶ If this is not possible, bends should be viewable from
both directions.
600mm radius
600 mm
600 mm
750 mm
2250 mm
2250 mm
600 mm
2250 mm
600mm radius
750 mm
2250mm
6720643895-10.1Wo
11
1
1
2 2
2
2

Pre-Installation
6 720 811 922 (2014/07)14
The flue systems have different maximum flue lengths
The Greenstar series has the option of two horizontal 60/100 RSF
(telescopic and longer telescopic) and one horizontal 80/125 RSF
(telescopic) flue system and two vertical RSF (60/100 or 80/125) flue
systems:
The next page shows various fluing options.
Refer to the Flue options in table 11 for the straight flue lengths required
to achieve the maximum flue length.
NOTICE: Effective flue lengths:
▶ each 90° bend is equivalent to 2 metres of straight
flue
▶ each 45° bend is equivalent to 1 metre of straight flue
The maximum plume management length for any flue
length for the appliances mentioned on the front of this
manual is 4.5 metres.
Plume management kits are available for the 60/100
horizontal flue system,
Part number 7 716 191 086.
Refer to the manual supplied with the Plume
Management kits for complete installation instructions
Greenstar 24/28/30 boilers
Maximum total flue
length L (mm)
FLUE TYPE 60/100 80/125
1 Telescopic horizontal flue assembly 130 - 570 405 - 600
Longer telescopic horizontal flue
assembly
570- 790 NA
2 Horizontal flue extension 4,600 15,000
3 Horizontal flue with 1 x 90° bend 2,600 13,000
4 Horizontal flue with 2 x 90° bends N/A 11,000
5 High level horizontal flue 4,600 15,000
6 High level horizontal flue with 2 x 90°
bends
2,600 13,000
7 High level horizontal flue with 3 x 90°
bends
N/A 11,000
8 Vertical balanced flue assembly 6,000 15,000
9 Vertical balanced flue with 2 x 90° bends 2,000 11,000
10 Vertical balanced flue with 2 x 45° bends 4,000 13,000
Table 11 Flue options
Part number Flue Description
7 716 191 082 60/100 Telescopic horizontal flue assembly
7 716 191 171 60/100 Longer telescopic horizontal flue
assembly
7 719 003 702 80/125 Telescopic horizontal flue assembly
7 719 002 430 60/100 Vertical flue assembly
7 719 002 431 80/125 Vertical flue assembly
Table 12 Flue part numbers

Pre-Installation
6 720 811 922 (2014/07) 15
Fig. 17
350 mm - 570 mm
130 mm Min
Flat roof
300 mm
500 mm
Pitched
roof
2
3
4
5
6
10
9
8
7
1
6720643895-12.1Wo

Pre-Installation
6 720 811 922 (2014/07)16
3.8 FLUE TERMINAL POSITIONS
Fig. 18 Flue terminal positions
Key to illustration
1. 300mm adjacent to a boundary line.
2. The dimension below eaves, balconies and car ports can be reduced
to 25mm, as long as the flue terminal is extended to clear any
overhang.Anyexternalfluejointsmustbe sealedwithsuitable silicon
sealant.
3. 1,500mm between a vertical flue terminal and a window or dormer
window.
4. 1,200mm between terminals facing each other.
5. Vertical flue clearance, 300mm adjacent to a boundary line.
6. 600mm distance to a boundary line, unless it will cause a nuisance.
BS 5440:Part 1 recommends that care is taken when siting terminal
in relation to boundary lines.
7. 600mm minimum clearance from a skylight to a vertical flue.
8. Vertical flue clearance, 500mm to non-combustible building
material, and 1,500mm clearance to combustible building material.
9. 300mm above, below and either side of an opening door, air vent or
opening window.
10.600mm diagonally to an opening door, air vent or opening window.
11.300mm to an internal or external corner.
12.2,000mm below a Velux window, 600mm above or to either side of
the Velux window.
13.400mm from a pitched roof or in regions with heavy snow fall
500mm.
14.500mm clearance to any vertical structure on a roof, 600mm to
room sealed flue or 1,500 to an open flue.
15.200mm below eaves and 75mm below gutters, pipe and drains.
16.The dimension below eaves, balconies and car ports can be reduced
to 25mm, as long as the flue terminal is extended to clear any
overhang.Anyexternalfluejointsmustbe sealedwithsuitable silicon
sealant.
17.Flue clearance must be at least 300mm from the ground. Terminal
guards must br fitted if the flue is less than 2 metres from the ground
or if a person could come into contact with the flue terminal.
18.600mm distance to a surface facing a terminal, unless it will cause a
nuisance. BS 5440: Part 1 recommends that care is taken when
siting terminals in relation to surfaces facing a terminal.
16
600
300
200
300
1,200
Boundary Line
1,500
1,500
All measurements in millimetres
2
1
12
11
10
9
5
18
7
6
13
15
4
3
17
14
300 300
300 300
300
300 300
500
600
300
600
600
400
300
25
8
300
500
600
6720643895-13.3Wo
300
25
225 16
2m
1m
52mm 104mm
NOTICE:
▶ All measurements are the minimum clearances required.
▶ Terminals must be positioned so to avoid combustion products entering the building.
▶ Support the flue at approximately one metre intervals and at a change of direction, use suitable brackets and fittings (flue brackets
100mm x 6 part number:7 716 191 173, flue bracket 125mm part number: 7 716 191 174).
Note:
▶ Installations in car ports are not recommended.
▶ The flue cannot be lower than 1,000mm from the top
of a light well due to the build up of combustion
products.
▶ Dimensions from a flue terminal to a fanned air inlet
to be determined by the ventilation equipment
manufacturer.

Pre-Installation
6 720 811 922 (2014/07) 17
3.9 PLUME MANAGEMENT TERMINAL POSITIONS
Fig. 19 Plume terminal positions
Key to illustration
1. This feature allows some basic plume re-direction options on a
standard telescopic horizontal flue terminal.
300mm minimum clearances to a opening e.g. window.
However the minimum clearances to an opening in direction that the
plume management is facing, must be increased to 1,500mm.
Where the flue is less than 150mm to a drainpipe and plume re-
direction is used the deflector should not be directed towards the
drainpipe.
2. 300mm adjacent to a boundary line.
3. Plume Management Kit air intake can be reduced to 150mm
providing the flue exhaust outlet is noless than 300mm adjacent to a
boundary line.
4. 1,200mm between terminals facing each other.
5. 600mm distance to a boundary line, unless it will cause a nuisance.
BS 5440:Part 1 recommends that care is taken when siting terminal
in relation to boundary lines.
6. Using a Plume Management Kit the air intake measurement can be
reduced to 150mm providing the flue exhaust outlet has a 300mm
clearance.
Plume kits running horizontally must have a 10° fall back to the boiler
for proper disposal of condensate.
For details on specific lengths see relevant boiler Technical &
Specification information.
7. Internal/external corners. The air intake clearance can be reduced to
150mm providing the flue exhaust outlet has a 300mm clearance.
8. Clearances no less than 200mm from the lowest point of the balcony
or overhang.
9. 1,200mm from an opening in a car port on the same wall e.g. door or
window leading into the dwelling.
10.600mm distance to a surface facing a terminal, unless it will cause a
nuisance. BS 5440: Part 1 recommends that care is taken when
siting terminals in relation to surfaces facing a terminal.
200
300
150
200
8
4
5
3
2
9
200
600
All measurements in millimetres
300
300
150
150
300
300
25
25
150
1,200
300
200
10
100
600
Plume re-direction:
180°
±80°
1
7
±45°
Flue Exhaust
Outlet
Air Intake
6
10
Boundary Line
6720643895-14.2Wo
150
300
300
Flue terminal guard 7 716 191 176
600
1,500
The minimum plume management length for any length of flue is 500mm and the maximum length is 4.5 metres for the appliances
detailed on the front of this manual.
The 45° bend is equivalent to 0.75 metres of straight plume management and the 90° bend is equivalent to 1.5 metres.
NOTICE:
▶ All measurements are the minimum clearances required.
▶ Refer to figure 15 for all concentric flue terminal positions unless the flue position is specified on the figure above “Plume terminal
positions”.
▶ Terminals must be positioned so to avoid combustion products entering the building.
▶ Support the flue at approximately one metre intervals and at a change of direction, use suitable brackets and fittings.
Note:
▶ Installations in car ports are not recommended.
▶ The flue cannot be lower than 1,000mm from the top
of a light well due to the build up of combustion
products.
▶ Dimensions from a flue terminal to a fanned air inlet
to be determined by the ventilation equipment
manufacturer.

Installation
6 720 811 922 (2014/07)18
4INSTALLATION
IMPORTANT HANDLING INSTRUCTIONS
• It is advised that two people are used to carry the carton from the van
to the point of delivery.
ADDITIONAL REQUIREMENTS FOR ROOF SPACE INSTALLATION
• Unpack the boiler before going up the ladder into the loft space.
• Two sets of ladders/steps should be used.
• Two people should share the lifting of the boiler up to the loft hatch,
put the boiler into the loft space, tilt and slid on its back into the loft.
• Once the appliance is removedfrom its packagingcheckthecontents
against the packing list.
4.1 UNPACKING
1. Cut through the tape securing the top flaps of the carton
2. Lift out the two accessory trays.
Fig. 20 Remove accessories
[1] Outer packaging
[2] Hand holds
[3] Top tray
[4] Bottom tray
3. Lay down the appliance on its back and cut through the tape securing
the bottom flaps of the carton.
4. Fold the flaps back and stand the appliance up right
5. Lift the carton off the appliance.
Fig. 21 Remove the carton
[5] Appliance
[6] Base tray
6. Remove the plastic bag covering the appliance.
7. Lay the appliance down on its back and remove the base tray.
WARNING: All the previous “Pre- Installation” sections
must be read and the requirements met before starting
boiler or flue installation.
DANGER: Risk of explosion
▶ Isolate the gas supply before working on gas related
components.
▶ Check for leaks before working on gas related
components.
NOTICE:
▶ Before installing the appliance, ensure that the
system has been cleaned as explained on page 8
CAUTION: LIFTING AND CARRYING
▶ Only lift a manageable weight, or ask for help.
▶ Bend your knees and keep your back straight with
feet apart, when lifting or putting down heavy
objects.
▶ DO NOT lift and twist at the same time.
▶ Lift and carry object close to the body.
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Installation
6 720 811 922 (2014/07) 19
Fig. 22 Remove cover and base
4.2 WALL MOUNTING TEMPLATE & FLUE OPENING
SAFETY:
All relevant safety precautions must be undertaken. Protective clothing,
footwear, gloves and safety goggles must be worn as appropriate.
MOUNTING ON THE WALL
No special wall protection is required. The wall must be flat and able to
bear the weight of the appliance.
▶ Fix the wall mounting template, supplied with the literature pack, to
the wall, allowing a side clearance of at least 10 mm on each side
(Fig. 15) .
▶ Drill holes for wall plugs and mounting plate to match the mounting
template.
▶ Drill the two holes for mounting the plumbing manifold.
▶ If required: make a hole in wall for the flue pipe.
REAR FLUE OUTLET
The drawing opposite shows the boiler wall mounting template with the
flue centre lines of both the 100mm and 125mm flue systems.
▶ Mark the centre line of the flue to be used (3); the external diameter
of the hole can also be marked if required.
▶ If a 100mm diameter flue is to be used, a 125mm diameter hole is
required. However, if using the weather sealing collar by pushing it
through from inside the property, then a 150mm diameter hole is
required to accommodate this.
• The flue turret of the 100mm flue has an in-built 3° angle.
• If extensions are to be added then the complete flue must rise at an
angle of 3°.
▶ Drill the hole, preferably using a core drill.
SIDE OUTLET
▶ Mark from the centre line of the wall mounting template to the wall
that the flue will pass through (4).
• Allow for a rise of 52mm per metre length of flue, to give a 3° angle.
• Clear any debris from the site.
Standard package contents:
Top Tray
Isolating valve bracket
Bottom Tray
Literature pack:
- Installation instructions
- User guide
- PRV installer connection
- Condensate adapter
- Wall mounting template
Hardware pack:
- Compression fittings
- Fibre washers
Top wall hanging bracket
Fascia flap
Table 13
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WARNING: BEFORE DRILLING ENSURE THAT THERE
ARE NO PIPES, ELECTRICAL CABLES, DAMP PROOF
COURSES OR OTHER HAZARDS.
NOTICE: Never carry the appliance by the control box or
rest the full weight of the appliance on it.

Installation
6 720 811 922 (2014/07)20
Fig. 23 Mounting template
▶ Remove the mounting template.
▶ Fit wall plugs and secure the mounting plate with appropriate fittings
for the boiler weight and wall type.
▶ Fit the wall plugs and secure the plumbing manifold with appropriate
fittings.
4.3 PRE-PLUMBING THE BOILER CONNECTIONS
▶ Remove the fittings on the connecting pipes.
GAS AND WATER CONNECTIONS - ISOLATING VALVE BRACKET
▶ Ensure that the fibre washers, supplied in the literature/hardware,
are fitted to the connections to the isolating valves.
▶ Ensure that the bonded washer isfitted to the gas pipe isolating valve
connection.
Fig. 24 Isolation valves
[1] CH flow 22mm
[2] DHW Outlet (15mm)
[3] Gas inlet (22mm bonded washer)
[4] Domestic cold water inlet (15mm)
[5] CH return 22mm
▶ All pipe connections in the heating system must be suitable for a
pressure of 3 bar and for 10 bar in a hot water DHW circuit.
▶ For filling and draining the system, fit drainvalves at the lowest point
of the system.
▶ Fit an air vent valve at the highest point.
4.4 HANGING THE BOILER
REMOVING THE OUTER CASING
1. Remove the two securing screws underneath the appliance.
2. Slide outer casing from the bottom forwards and lift.
NOTICE: The appliance can be damaged by debris in the
pipework.
▶ Flush the system to remove all debris/residue.
WARNING: Bonded washer for gas (3)
▶ The bonded washer must be used on the gas pipe
isolating valve connection.
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3.
2.
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6 720 811 922-05.1O
CAUTION: Lifting the boiler.
▶ There are two handling holes incorporated into the
inner casing left and right in the lower section of the
appliance.
▶ Do not lift the boiler using the control panel as a hand
hold.
NOTICE: Hanging the boiler.
▶ Remove the plastic strip fitted to pipes before
hanging the boiler.
Please protect the floor from residual water.
The outer casing is secured against unauthorised
removal by two screws (electrical safety).
▶ Always secure the outer casing with these screws.
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