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.
The following keywords are defined and can be used in this document:
• NOTICE 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
This symbol indicates important information where
there is no risk to people or property.
Additional symbols
SymbolMeaning
a numbered step in an action sequence
a step in an action sequence
a reference to a related part in the document or to other
related documents
a reference number to identify or refer to a part or item
1
a list entry
a list entry (second level)
Table 1 Symbols
Examples of additional symbols used
A numbered step in an action sequence
A sequence of numbered steps or actions carried out in a specific order
to complete a task.
1. First action
2. Second action
3. Third action
etc.
A step in an action sequence
A sequence of defined actions or steps carried out in order to complete
a task.
▶Action
▶ Next action
▶etc
A reference to a related part in the document or to other related
documents.
To refer the reader to a specific figure/table/section within the manual.
e.g. figure 1.
A reference number to identify or refer to a part or item.
In a related figure, items or parts identified by a sequential number.
List entries, first and second levels
• A single component/item
• A component/list, made up of multiple parts/items.
– Sub component or sublist of main component/list.
–etc.
SYMBOLS USED IN THIS MANUAL
Domestic Hot Water
Central Heating
Hot Water Storage Cylinder
Domestic Cold Water Supply
Electrical Supply
Gas Supply
Table 2 Commonly used symbols
PLEASE READ THESE INSTRUCTIONS CAREFULLY BEFORE
STARTING INSTALLATION.
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 and serviced 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
(0330 123 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.
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KEY TO SYMBOLS AND SAFETY INSTRUCTIONS
ØDiameter
NGNatural Gas
LPGLiquid Petroleum Gas
CHCentral Heating
DHWDomestic Hot Water
DCWDomestic Cold Water
DWTADomestic Water Treatment Association
PRVPressure Relief Valve
NTCNegative Temperature Coefficient (sensor)
IPIngress Protection
RCDResidual Current Device
TRVThermostatic Radiator Valve
ECVEmergency Control Valve
WRASWater Regulations Advisory Scheme
SEDBUKSeasonal Efficiency of Domestic Boilers in the United
Kingdom
Table 3 Abbreviations use in this manual
1.2Safety 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 or regulator.
▶ 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.
▶ L.P.G. boilers: Call the supplier’s number on the side of the gas tank.
Appliance operation:
This appliance can be used by children aged from 8 years and above and
persons with reduced physical, sensory or mental capabilities or lack of
experience and knowledge, if they have been given supervision or
instruction concerning the use of the appliance, in a safe way, and
understand the hazards involved.
Children shall not play with the appliance.
Cleaning and user maintenance shall not be made by children without
supervision.
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 warranty.
Fittings 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 warranty. 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.
Flue System
Only use the approved Worcester Condensfit II flue system with this
appliance.
Worcester original spare parts
Only use Worcester original spare parts with this appliance.
Non Worcester original spare parts will invalidate the guarantee (if
applicable) and any warranty.
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.
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.
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REGULATIONS
2Regulations
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, IET 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), EU Regulations No. 811/
2013 - Energy Labelling and any other local requirements.
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)
L.P.G. Installations
An appliance using L.P.G. must not be installed in a room or internal
space below ground level unless one side of the building is open to the
ground.
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 Buildings
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.
CH Water
Artificially softened water must not be used to fill the central heating
system.
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3APPLIANCE INFORMATION
* 690mm to top of case front
680mm*
390mm
280mm
6720813280-02.1Wo
2
6
7
Depth to wall
(When fitted to wall frame)
3
1
5
4
3.1Appliance
APPLIANCE INFORMATION
STANDARD PACKAGE
1. Wall hung gas-fired condensing system boiler for central heating and domestic hot water
2. Wall mounting frame
3. Hardware literature pack:
– Greenstar i System Compact
–User guide
– Boiler fascia guide
– Wall mounting template
– Condensate connector
– Sealing Pack
4. ErP Label
5. PRV Installer connection elbow
6. Bottom panel
7. Fascia panel
ErP
Installation, Commissioning and Servicing Instructions
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APPLIANCE INFORMATION
3.2TECHNICAL DATA
DESCRIPTION i System Compact
Natural GasL.P.G.
UNIT27kW30kW27kW30kW
Gas flow rate - Max. 10 minutes from lighting
Natural Gas G20m³/h2.923.24
L.P.G.kg/h2.12.33
Heating
Minimum heat inputkW7.157.157.157.15
Maximum rated heat input (net)kW27.5830.6527.5830.65
Maximum rated heat output 40/30 °CkW28.5531.7028.5531.70
Maximum rated heat output 50/30 °CkW28.431.5728.431.57
Maximum rated heat output 80/60 °CkW27.030.027.030.0
Maximum flow temperature°C82828282
Maximum possible flow temperature°C86868686
Maximum permissible operating pressurebar2.52.52.52.5
Available pump head at 21°C system temperature risem2.02.02.02.0
Flue
Flue gas temperature 80/60 °C, rated/min. load°C67/6470/6469/6672/66
Flue gas temperature 40/30 °C, rated/min. load°C48/3650/3650/3752/37
CO2 level at max. rated heat output (after 30 minutes)%9.19.110.610.6
CO2 level at min. rated heat output (after 30 minutes)%8.58.59.69.6
NOx class 5555
NOx ratingmg/kWh35354042
Condensate
Maximum condensate ratel/h2.52.52.52.5
pH value, approx.4.84.84.84.8
Electrical
Electrical power supply voltagea.c. V230230230230
FrequencyHz50505050
Maximum power consumption - runningW102109102109
Maximum power consumption - stand-byW1111
General data
Appliance protection ratingIPX4DX4DX4DX4D
Appliance protection rating with FW100 module fitted*IPIP20IP20IP20IP20
Appliance protection rating with Sense II module fitted*IPIPX2DIPX2DIPX2DIPX2D
Permissible ambient temperatures°C0 - 500 - 500 - 500 - 50
Nominal capacity of appliancelitre2.12.12.12.1
Total boiler weightkg37.537.537.537.5
Lift weightkg27.327.327.327.3
SEDBUK 2005BandAAAA
SEDBUK 2009%89.089.090.090.0
Table 4 Technical data i System Compact
* used with the optional integral diverter valve kit.
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APPLIANCE INFORMATION
3.3ENERGY EFFICIENCY
The following product data satisfy the requirements of the EU Regulations No. 811/2013 and No. 812/2013 supplementing Directive 2010/30/EU.
Condensing boiler––YesYesYesYes
Low temperature boiler––NoNoNoNo
B1 boiler––NoNoNoNo
Cogeneration space heater (CHP)––NoNoNoNo
Combination heater––NoNoNoNo
Rated heat outputP
Seasonal space heating energy efficiency
kW27302730
rated
%92929292
s
Energy efficiency class––AAAA
Useful heat output
At rated heat output and high temperature regime
At 30% of rated heat output and low temperature
2)
regime
1)
P
P
kW27302730
4
kW8.99.98.99.9
1
Useful efficiency
At rated heat output and high temperature regime 1)
At 30% of rated heat output and low temperature
2)
regime
%88.288.288.288.2
4
%97.397.397.397.3
1
Auxiliary electricity consumption
At full loadel
At part loadel
In standby modeP
kW0.0330.040.0330.04
max
kW0.0140.0140.0140.014
min
kW0.0010.0010.0010.001
SB
Other items
Standby heat lossP
Ignition burner power consumptionP
kW0.0780.0780.0780.078
stby
kW0000
ign
Emissions of nitrogen oxidesNOxmg/kWh32323232
Annual energy consumptionQ
Sound power level, indoorsL
kWh----
HE
dB(A)53555355
WA
Table 5 Product data for energy consumption according to the EU regulations no. 811/2013 and no. 813/2013
1) High-temperature regime means 60 °C return temperature at heater inlet and 80 °C feed temperature at heater outlet.
2) Low temperature means for condensing boilers 30 °C, for low-temperature boilers 37 °C and for other heaters 50 °C return temperature (at heater inlet).
NG
27i System
Compact
ErP
LPG
Compact
ErP
LPG
30i System
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APPLIANCE INFORMATION
6720813280-03.1Wo
44434241 40
39
38
37
36
35
27
50
49
48
47
45
46
30
29
28
31
7
32
34
9
33
8
11
12
13
14
1
2
3
4
5
6
1617
18
19
20
2324
22
25
26
15
21
10
3.4LAYOUT
Fig. 1 Main boiler components
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1Wall mounting frame26Boiler display
2Expansion vessel27Fan
3CH return isolator28Flow temperature sensor (NTC)
4Gas inlet isolator29Electrode assembly
5CH flow isolator30Maximum safety sensor NTC
6Condensate connection31Auto air vent
7Flue connector32Aluminium Silicon Heat exchanger
8Case retaining clips33Flueway
9Flue overheat thermostat34Sump assembly
10Air Pressure Switch35Pressure gauge connection point
11Main superstructure36Diverter valve actuator blank
12Case37Diverter valve body
13Case retaining screws38Modulating pump
14Bottom panel39Drain point
15Control, top panel40CH return connection to service valve
16Menu buttons41PRV
17Blank for optional programmer42Gas connection to service valve
18Diagnostic port (for Worcester service engineers)43CH flow connection to service valve
19Pressure gauge44Condensate discharge pipe
20DHW temperature control*45Siphon
21Boiler identification label46Expansion vessel connection point
22Operation/fault diagnostic light (blue)47Return temperature sensor (NTC)
23Control panel flap48Gas valve
24Boiler fascia guide location49Combustion air inlet
25CH temperature control50Ignition transformer
Table 6 Boiler components
PRE-INSTALLATION
* DHW temperature control.
The optional Integral Diverter Valve kit with cylinder
sensor is required to enable the hot water temperature
control to be used.
The table below lists:
▶ the accessories that can be fitted when the integral
diverter valve is fitted.
▶ with which accessory the DHW control is exclusively
responsible for the stored DHW temperature.
DHW control exclusively
responsible
Accessory
Integral diverter
valve
External diverter
valve
DT10 RF DigistatYESN/A
DT10 RF OptimiserYESN/A
DT20YESN/A
DT20 RFYESN/A
FR110NON/A
FW100NON/A
Comfort I RFYESN/A
Comfort II RFYESN/A
ComfortYESN/A
Sense IYESN/A
Sense IINON/A
Worcester WaveYESN/A
Table 7
The FR110, FW100 and Sense II provide an additional
level of control over the DHW set point, allowing the DHW
set point to be adjusted at these controls and not only via
the DHW temperature control knob on the boiler’s facia.
With these controls, the boiler facia’s control knob,
becomes the maximum temperature limiter. If this is set
too low, the DHW set point on the control cannot be
achieved.
4PRE-INSTALLATION
4.1CLEANING PRIMARY SYSTEMS
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: Water treatment
▶ 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.
▶ It is recommended that you fit a primary water
cleanser to the system. Worcester recommends
fitting a filter that will help remove both magnetite and
non-magnetic debris.
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PRE-INSTALLATION
BEFORE CLEANING THE SYSTEM:
▶ Ensure that the system and pipework 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.
NOTICE: Artificially softened water must not be used to
fill the central heating system.
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.
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.
WATER TREATMENT PRODUCTS
Suitable water treatment products can be obtain from the following
manufacturers:
• FERNOX- 0870 601 5000 or www.fernox.com
• SENTINEL - 0800 389 4670 or www.sentinel-solutions.net
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.
4.2MAINS SUPPLY
4.2.1 ELECTRICAL SUPPLY
• Supply: 230V - 50 Hz
• Cable: PVC insulated 0.75mm2 (24 x 0.2mm) 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.
NOTICE: IP rating change;
This is reduced to IP20 if the following control is fitted
FW100 7 716 192 067.
This is reduced to IPX2D when the Sense II
7 738 111 064 is fitted.
• Wiring must comply with the latest edition of BS 7671 (IET wiring
regulations).
4.2.2 GAS SUPPLY
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, the following applies:
• Boilers using Natural Gas (NG) must be connected to a governed
meter.
• Liquid Petroleum Gas (LPG) must be connected to a regulator.
• Installation and connection of the gas supply to the boiler must be in
accordance with BS6891.
• Gas pipe sizing should be calculated to ensure no more than the
permitted mbar drop between the meter/governor to the appliance
inlet. ( Commissioning section).
• The meter or regulator and pipe work to the meter must be checked,
preferably by the gas supplier.
4.3WATER SYSTEMS AND PIPEWORK
PLASTIC PIPEWORK:
• Any plastic pipework must have a polymeric barrier with 600mm
(min.) length of copper pipe before being connected to the boiler.
• Plastic pipework 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 with the room thermostat.
• 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.
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).
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PRE-INSTALLATION
CV = Check Valve
SV = Stop Valve
SVSV
Test point
Temporary hose
Hose union
CV
CV
Heating
return
Mains
supply
SYSTEM MAKE UP
AA = Auto Air vent
CV = Check Valve
SV
CV
AA
Make up
vessel
Heating
return
1000 mm (39 in)
above the highest
point of the system.
6720644743-08.2Wo
1
2
3
6720644743-09.1Wo
3
2
1
4
M
M
3
2
1
M
6720646609-33.1Wo
Heating flow
Cylinder return
Cylinder flow
Heating return
F
R
3
2
F
R
3
2
1
4
M
MM
SEALED PRIMARY SYSTEM:
NOTICE: Artificially softened water must not be used to
fill the central heating system.
• The CH sealed system must be filled using a WRAS approved filling
loop or comply with figure 2 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
NOTICE: Automatic bypass
▶ An automatic bypass valve is required when fitting an
S-plan type system with two-port valves.
NOTICE: Drain cock
▶ A drain cock should be fitted at the lowest point(s) of
This boiler is designed to operate on a sealed system only. The boiler will
require a second return pipe from the water cylinder to the wall
mounting frame and terminate in 15mm copper pipe.
4.3.1 S AND Y PLAN SYSTEMS
The boiler is equipped with an internal by-pass.
Greenstar i System Compact
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).
SYSTEM LAYOUT WITH OPTIONAL INTERNAL DIVERTER VALVE
(NOT SUPPLIED WITH BOILER)
In order to save as much energy as possible and the
minimise the possibility of water circulation noise, a low
characteristic should be chosen.
The pump map can be selected within 2.1C in the Boiler settings menu
list:
• 0 (pump variable speed setting)
• 1 (constant pressure low)
• 2 (constant pressure low/middle)
• 3 (constant pressure middle/high)
• 4 (constant pressure high)
The factory setting is:
4 (constant pressure high)
CONSTANT PRESSURE HEAD
If the constant pressure head option (1 - 4) is chosen, the differential
pressure between the CH flow and return will be kept at the
corresponding value. When the CH system is cold and the radiator TRVs
are fully open, the pump will be running faster to try and maintain the
pressure differential. When the TRVs start to close and the resistance of
the CH system increases, the pump speed reduces to maintain the
pressure.
The setting (1 - 4) to be selected is dependent upon the resistance and
heat load of the CH system. The higher these are, the higher the pressure
constant
4.4.1 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. 4 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.
4.4CONDENSATE PIPEWORK
NOTICE:
▶ Where a new or replacement boiler is being installed,
access to an internal “gravity discharge” point should
be one of the factors considered in determining boiler
location.
▶ The condensate pipe must be nominally
22mm Ø plastic pipe.
▶ The condensate pipework 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
1Condensate discharge from boiler
2Soil and vent stack
3Minimum 450mm and up to three storeys
4Visible air break at plug hole
5Sink or basin with integrated overflow
675mm sink waste trap
7Condensate pump
*Condensate trap of 75mm already incorporated into the boiler
Fig. 5 Disposal to a waste pipe
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PRE-INSTALLATION
75mm
min.
4
7
5
6
1
22mm Ø
6720644744-08.3Wo
188
13
14
17
15
16
1
6720644744-09.3Wo
25mm min.
14
13
1
6720644744-10.3Wo
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.
▶ 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, if not
using a CondenseSure siphon.
▶ The external pipe should take the shortest and least exposed route to
the discharge point, and should "fall" as stee ply as po ssib le a way f rom
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 pipework should be removed so that the
internal pipe section is as smooth as possible.
FITTING AN EXTERNAL AIR BREAK
• Refer to figure 7 when a rain water down pipe is used to dispose of
condensate.
• An air break must be installed in the 43mm pipework, between the
boiler condensate outlet and the drainpipe, outside the property, to
avoid flooding during adverse weather conditions.
Fig. 6 Condensate pump disposal
4.4.2 EXTERNAL CONNECTIONS
NOTICE: Freezing conditions
▶ When the position of the boiler prevents internal
routing, we recommend installing a CondenseSure
siphon to significantly reduce the risk of freezing.
▶ Pipework length should be kept to a minimum and the
route as vertical as possible.
▶ Weather proof insulation must be used, if not using a
CondenseSure siphon.
NOTICE: Condensate waste
▶ Care should be taken when siting a soak-away to avoid
obstructing existing services.
Continued - Key to condensate illustrations
8PVCu strap on fitting
9100mm Ø minimum plastic pipe
10Drainage holes
11Limestone chippings
12Bottom of sealed tube
13Insulate and increase pipe size
14Pipework transition
15External air break
16Air gap
17External rain water pipe into foul water
1843mm 90° male/female bend
*Condensate trap of 75mm already incorporated into the boiler
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:
▶ Use a CondenseSure siphon to help prevent the condensate freezing.
▶ The external run be kept as short as possible and not exceed 3 metres.
ErP
Greenstar i System Compact
- 6 720 813 280 (2015/07)15
Fig. 7 Disposal into a rainwater down pipe
Condensate drainage pipe can be run above or below
ground.
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. 8 External disposal
PRE-INSTALLATION
25mm min.
14
13
1
7
6720644744-12.3Wo
13
14
10
500mm min.
25mm min.
400mm
min.
1
12
11
9
6720644744-11.2Wo
9
10
*
1
2
3
4
2
3
4
1
2
6720646608-123.1Wo
Fig. 9 Condensate pump to 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.
Minimum hole size for the condensate soak away m ust be
400mm deep by 300mmØ .
4.5PRESSURE RELIEF PIPEWORK
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.
• 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.
In situations where there are likely to be extremes of temperature or
exposure, the use of a proprietary trace-heating system for external
pipework, 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.
NOTICE: Unheated internal areas.
▶ Internal pipe runs in unheated areas such as lofts,
basements and garages should be treated as external
runs and consideration should be given to using a
CondenseSure siphon.
This appliance 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
appliance and capable of supporting the appliance weight.
No surface protection is required against heat transfer
from the appliance.
The appliance must be installed where:
• An engineer can gain clear and safe access to work on the product or
component, including making adequate provision for visual
inspection of flues in voids.
• The homeowner can gain clear and safe access to the controls,
check, top up or reset the appliance.
• Products in loft cavities must have permanent fixed lighting, a
permanent fixed retractable ladder and a fixed floor area sufficient to
allow access for normal use and servicing directly under and around
the product and between and the access hatch.
4.6.2 INSTALLATION AND SERVICING CLEARANCES
PRE-INSTALLATION
4.6.4 BATHROOMS
Please check the IP rating of any control to be used on this appliance.
Only certain controls can be fitted when the appliance is inside of the
shaded area.
An appliance with blanking panel or controls that do not change the IP
rating can be installed in zone 2.
Additional RCD (Residual Current Device) protection may be required.
Consult the latest version of BS7671 (IET wiring regulations).
2* Without the end wall, zone 2 must extend 600mm from the bath
Fig. 12 Unventilated compartment
[*]Minimum clearance to removable door
[**]Minimum clearance required for servicing
[***] Height for either 60/100 flue or 80/125 flue
4.6.3 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.
Fig. 13 Bathroom installations
4.7PLUMBING MANIFOLD
4.7.1 CONNECTIONS
• If the boiler pipes are to be run behind the appliance ensure that the
pipes pass either side of the expansion vessel as shown in figure 15.
Further guidance on pipe routing can be found printed
on the boiler template (supplied with the boiler).
• For further ease of fitting, an optional Vertical Pre-piping Assembly kit
is available, comprising three pre-formed copper pipes and a cross
bonding strip. Part number: 7 716 192 712.
Heating System22mm compression fittings
Gas22mm compression fittings
Condensate22mm rubber push fit connector
PRV15mm (fittings not supplied)
Use the fittings supplied in the Hardware literature pack.
Greenstar i System Compact
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4.8FLUE TERMINAL POSITIONS
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
2
25
16
2m
1m
52mm
104mm
PRE-INSTALLATION
Fig. 16 Flue terminal positions
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.
Key to illustration
1. 300mm adjacent to a boundary line.
2. The dimension below eaves, gutters, pipes and drains can be
reduced to 25mm, as long as the flue terminal is extended to clear
any overhang. External flue joints must be sealed with suitable
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 unless it
will cause a nuisance. BS 5440:Part 1 recommends that care is
taken when siting terminal in relation to boundary lines
6. 600m 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. This does not apply to
building protrusions less than 450mm.
12. 2,000mm below a Velux window, 600mm above or to either side of
the Velux window.
13. 400mm from a pitched roof or 500mm in regions with heavy snow
fall.
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.
Greenstar i System Compact
(flue bracket 100mm part number: 7 716 191 177,
flue brackets 100mm x 6 part number: 7 716 191 178,
flue bracket 125mm part number: 7 716 191 179).
ErP
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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. External flue joints must be sealed with suitable
silicon sealant.
17. Flue clearance must be at least 300mm from the ground. Terminal
guards must be 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.
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.
▶ A flue terminal guard should be fitted over a terminal,
if persons could come into contact with the terminal,
or it could be subject to damage and where the
terminal is less than 2,000mm from the finished floor
level.
PRE-INSTALLATION
6720806945-29.1Wo
383 mm - 603 mm
60/100 mm
130 mm Min
350 mm - 570 mm
60/100 mm
130 mm Min
6720806945-19.1Wo
4.9FLUE OPTIONS
WARNING: Flue systems
▶ Only use Worcester, Bosch approved flue systems, no
other manufacturer’s flue systems have been
approved for use with Worcester appliances.
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.
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
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
Horizontal flue with additional elbow (1 x 90 ° bend)
4.9.1Flue lengths
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:
Refer to the following example Flue options for the maximum flue
lengths.
Horizontal high level flue assembly
Flue length (mm)
Horizontal high level telescopic flue assembly 202 - 603 N/A
Table 10
60/10080/125
Maximum flue length
(mm)
60/10080/125
Horizontal flue with 1 x 90° bend4,00013,000
Table 13
Horizontal flue with additional elbows (2 x 90 ° bends)
6720806945-21.1Wo
Maximum flue length
(mm)
60/10080/125
Horizontal flue with 2 x 90° bends2,00011,000
Table 14
Greenstar i System Compact
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- 6 720 813 280 (2015/07)20
PRE-INSTALLATION
6720806945-24.1Wo
A
6720806945-26.1Wo
6720806945-27.1Wo
High level horizontal flue
Maximum flue length
(mm)
60/10080/125
High level horizontal flue6,00015,000
Table 15
High level horizontal flue with additional elbows
Vertical balanced flue assembly
= 300 mm
B = 500 mm
6720806945-25.1Wo
Maximum flue length
(mm)
60/10080/125
Vertical balanced flue assembly6,00015,000
Table 18
Vertical balanced flue with elbow offset (2 x 90 ° bends)
Maximum flue length
(mm)
60/10080/125
High level horizontal flue with 2 x 90° bends 4,00013,000
Table 16
High level horizontal flue with additional elbows
Maximum flue length
(mm)
60/10080/125
High level horizontal flue with 3 x 90° bends 2,00011,000
Table 17
6720806945-23.1Wo
Maximum flue length
(mm)
60/10080/125
Vertical balanced flue with 2 x 90° bends2,00011,000
Table 19
Vertical balanced flue with elbow offset (2 x 45 ° bends)
Maximum flue length
(mm)
60/10080/125
Vertical balanced flue with 2 x 45° bends4,00013,000
Table 20
Greenstar i System Compact
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- 6 720 813 280 (2015/07)21
PRE-INSTALLATION
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:
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
4.10 PLUME MANAGEMENT TERMINAL POSITIONS
180°
±80°
Fig. 17 Plume terminal positions
Maximum and minimum plume management lengths:
▶ A minimum distance of 500mm must be maintained between the plume management outlet and the flue air intake.
▶ The maximum plume management 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 previous page 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.
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 the 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 redirection 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 no less 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. The initial horizontal run from the terminal elbow must
have a minimum 10° fall back, (stop tabs in the elbow prevent less
than 10°) to the appliance for proper disposal of condensate. Any
further horizontal runs can be 3°.
– For details on specific lengths see relevant appliance 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.
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.
Greenstar i System Compact
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- 6 720 813 280 (2015/07)22
4.10.1 DETERMINE THE PLUME MANAGEMENT SYSTEM LENGTH
67206646610-75.1Wo
5
0
0
m
m
5
0
0
mm
5
00
mm
±80°
0
500
1,500
2,500
3,500
4,500
1,000 2,000 3,000 4,000 5,000 6,000
Min
L
M
6720803800-08.1Wo
1
2
Effective straight flue length with plume management
Minimum plume length (M)
500mm
Maximum plume length (M)
4,500mm
Max flue length (L) 5,000mmMax flue length (L) 2,200mm
PRE-INSTALLATION
FLUE LENGTH VERSUS PLUME MANAGEMENT LENGTH
Note: Measurement M plume length
▶ M must be a minimum of 500mm and must not exceed
4,500mm for a 60mm plume management system
used with the horizontal Ø 60/100mm flue.
MINIMUM PLUME MANAGEMENT LENGTH
The minimum plume length should be calculated to ensure that the air
inlet and exhaust have a minimum distance of 500mm between them
( figure 18).
The plume management can be in any configuration, within the
parameters of the plume management installation instructions, as long
as it does not terminate inside the shaded area.
WARNING: Minimum plume management length.
The minimum distance of 500mm must be maintained
between air inlet and exhaust.
▶ Do not terminate the plume management inside the
shaded area shown in figure 18
M
L
6720803800-09.1Wo
Fig. 19 Effective lengths L and M
Fig. 18 Terminal exclusion zone
NOTICE: Cutting the 500mm pipe
If the 500mm plume management pipe kit is cut, an
additional elbow will be required to join the pipework.
▶ The Plume management extension kit contains the
components required for such a configuration.
Greenstar i System Compact
ErP
- 6 720 813 280 (2015/07)23
Fig. 20 Effective flue lengths versus plume management lengths