Worcester Greenstar Heatslave 12/18 User manual

INSTRUCTION MANUAL
INSTALLATION, COMMISSIONING & SERVICING
FLOOR STANDING OIL FIRED CONDENSING COMBINATION BOILER
CONVENTIONAL FLUE & ROOM SEALED FLUE
GREENSTAR HEATSLAVE
12/18, 18/25 & 25/32
FOR SEALED CENTRAL HEATING SYSTEMS WITH MAINS FED DOMESTIC
HOT WATER
UK
THE APPLIANCE IS FOR USE WITH KEROSENE
(28 SECOND OIL) ONLY

INSTALLATION &
SERVICING INSTRUCTIONS
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
2
SYMBOLS USED IN THIS MANUAL:
Domestic hot water
Central heating
Room thermostat
Frost thermostat
Wait time period
Programmer/timer OFF
INSTALLATION & SERVICING INSTRUCTIONS
IMPORTANT HANDLING INSTRUCTIONS:
It is advised that more than one person is
involved in the transfer of the packaged appli-
ance from the van to the point of installation.
It is advised that no attempt should be made to
move the packaged appliance without the use of
a suitable truck.
At all times the correct method for handling
heavy objects should be strictly observed.
GENERAL HANDLING GUIDELINES:
• Lift only a manageable weight, or ask for
help.
• When lifting, bend the knees, and keep the
back straight and feet apart.
• Do not lift and twist at the same time.
• Lift and carry items close to the body.
• Wear protective clothing and gloves to
protect from any sharp edges.
Programmer ON CH only
Programmer ON DHW only
Programmer ON CH and DHW
Cold water main supply
Electricity supply
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.
THE INSTRUCTIONS APPLY IN THE UK AND EIRE ONLY AND MUST BE FOLLOWED
EXCEPT FOR ANY STATUTORY OBLIGATION.
THIS APPLIANCE MUST BE INSTALLED BY A COMPETENT PERSON. FAILURE TO INSTALL
CORRECTLY COULD LEAD TO PROSECUTION.
COMPLYING WITH THE BUILDING REGULATIONS:
This heating appliance forms part of the controlled services for the building. It is law that all controlled
services for buildings must comply with building regulations. You must be able to satisfy your Local
Authority Building Control Body (LABC) that the work carried out concerning the installation and
commissioning of this heating appliance has been carried out to a satisfactory standard.
OFTEC operate a competent persons scheme and registered installers are able to certify that their
work complies with building regulations. Under the scheme;
lOFTEC must be informed about every installation.
lOFTEC will issue a building regulations compliance certificate to the householder and will
notify the LABC.
OFTEC provide controlled document forms CD10 and CD11 for use during installation and
commissioning respectively.
Other organisations operate self-certification schemes e.g. NAPIT and BESCA Ltd. and it may be
possible for installers who are members of these organisations to self certify their work.
Alternatively you must submit a building control notice to the LABC before installing any boiler. The
LABC will then arrange regular inspection visits during the work to ensure that the installation
complies with the regulations.
IF YOU ARE IN ANY DOUBT CONTACT THE WORCESTER TECHNICAL HELPLINE ON:
0844 892 366.
DISTANCE LEARNING AND TRAINING COURSES ARE AVAILABLE FROM WORCESTER.
PLEASE LEAVE THESE INSTRUCTIONS WITH THE COMPLETED COMMISSIONING FORM
AND THE USER MANUAL WITH THE OWNER OR WITH THE APPLIANCE AFTER
INSTALLATION OR SERVICING. THE SERVICE INTERVAL RECORD CAN BE FOUND ON
THE BACK PAGE OF THIS MANUAL.
ABBREVIATIONS USED IN THIS MANUAL:
Ø Diameter
CH Central Heating
DHW Domestic Hot Water
DCW Domestic Cold Water
TRV Thermostatic Radiator Valve
IP Ingress Protection
CF Conventional flue
BF Balanced flue
N/A Not allowed
SEDBUK Seasonal Efficiency of Domestic Boilers in the United Kingdom
OFTEC Oil Firing Technical Association for the Petroleum Industry
IEE Institute of Electrical Engineers
LABC Local Authority Building Control Body
STORE THE APPLIANCE IN A DRY AREA PRIOR TO INSTALLATION.
WATER TREATMENT:
FERNOX 01799 550811
fernox.com
SENTINEL 0800 389 4670
sentinel-solutions.net

SAFETY & REGULATIONS
IMPORTANT INFORMATION AND SYMBOLS 2
SAFETY PRECAUTIONS AND INSTALLATION REGULATIONS 4
APPLIANCE INFORMATION
GENERAL INFORMATION 5
TECHNICAL DATA 6
LAYOUT & COMPONENTS 7
PRE-INSTALLATION
CLEANING PRIMARY SYSTEMS 8
MAINS SUPPLY 9
OIL SUPPLY 10
WATER SYSTEMS & PIPEWORK 12
CONDENSATE PIPEWORK INTERNAL CONNECTION 14
CONDENSATE PIPEWORK EXTERNAL CONNECTION 15
CONDENSATE TO SOAK AWAY & PRESSURE RELIEF PIPEWORK 16
BOILER LOCATION & CLEARANCES 17
FLUE TERMINAL POSITIONS 19
CONVENTIONAL FLUE 20
ROOM SEALED FLUE OPTIONS 21
INSTALLATION
UNPACKING THE BOILER 22
PIPEWORK POSITIONS / FLUE OPENING 23
BOILER INSTALLATION 24
FLUE INSTALLATION 25
COMBUSTION CHAMBER 26
PIPEWORK CONNECTIONS 27
OIL BURNER AND PUMP 28
REFITTING COMPONENTS 29
ELECTRICS 30
COMMISSIONING
PRE-COMMISSIONING CHECKS - APPLIANCE 32
FILLING THE SYSTEM 33
STARTING THE APPLIANCE 34
WATER TREATMENT 39
FINISHING COMMISSIONING - APPLIANCE 40
SERVICING & SPARES
INSPECTION AND SERVICE 41
SHORT PARTS LIST RIELLO RDB 1 - 12/18 46
SHORT PARTS LIST RIELLO RDB 2.2 - 18/25 47
SHORT PARTS LIST RIELLO RDB 2.2 - 25/32 48
FAULT FINDING & DIAGNOSIS
ELECTRICAL SCHEMATIC 49
FAULT FINDING 50
FAULT FINDING LOGIC FOR RIELLO DIGITAL CONTROL BOX 52
COMMISSIONING CHECKLIST 54
SERVICE INTERVAL RECORD 55
CONTENTS
CONTENTS
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
3
SAFETY &
REGULATIONS
APPLIANCE
INFORMATION
PRE -
INSTALLATION
INSTALLATIONCOMMISSIONING
SERVICING
& SPARES
FAULT FINDING
& DIAGRAMS
NOTES

SAFETY PRECAUTIONS
& INSTALLATION REGULATIONS
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
4
SAFETY &
REGULATIONS
SAFETY PRECAUTIONS INSTALLATION REGULATIONS
OIL FUMES OR LEAKS FROM THE APPLIANCE:
✔ Extinguish any naked flames.
✔ Open windows and doors.
✔ Isolate the electrical supply.
✔ Isolate the fuel supply to the boiler.
✔ Rectify fault.
HEALTH & 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). Where applicable, the CE mark indicates compliance with relative EU
Directives.
COMBUSTIBLE AND CORROSIVE MATERIALS:
Do not store or use any combustible materials (paper, thinners, paints etc.) inside or within the
vicinity of the appliance.
The combustion air must be kept clear of chemically aggressive substances which can corrode
the appliance and invalidate any warranty.
FITTING & MODIFICATIONS:
Fitting the appliance and any controls to the appliance may only be carried out by a competent
engineer in accordance with these instructions and the relevant Installation 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 regularly serviced by a competent, qualified engineer (such
as OFTEC registered personnel) using approved spares, to help maintain the economy, safety
and reliability of the appliance.
IMPORTANT:
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.
Failure to install appliances correctly could lead to
prosecution.
The appliance should be installed by a competent
person. The person installing the appliance should
be aware of the Health and Safety at Work Act and
take appropriate action to ensure that the
regulations are adhered to. In order to give
optimum efficiency and trouble free operation the
appliance must be commissioned by a qualified
OFTEC engineer.
The compliance with a British Standard does not,
in itself, confer immunity from legal obligations. In
particular the installation of this appliance must be
in accordance with the relevant requirements of the
following British Standards and regulations in
respect of the safe installation of equipment:
BS 5410: part 1: Code of practice for Oil Fired
Boilers.
BS 799: part 5: Specification for Oil Storage
Tanks .
BS 7593: Code of Practice for treatment of water
in domestic hot water central heating systems.
BS 5449: part 1: Specification for forced
circulation hot water central heating for domestic
premises.
BS 5955: part 8: Specification for the installation
of thermoplastic pipes and associated fittings for
use in domestic hot and cold water services and
heating systems.
BS 7291: Thermoplastic pipes and associated
fittings for hot and cold water for domestic
purposes and heating installations in buildings.
BS 7074: part 1: Application, selection and
installation of expansion vessels and ancillary
equipment for sealed water systems.
BS 1254-2: Copper and copper alloys plumbing
fittings part 2: Fittings with compression ends for
use with copper tubes.
BS 7671: IEE Wiring Regulations, current edition.
BS 1362: Specification for general purpose fuse
links for domestic and similar purposes.
The Building Regulations Part G, Part J and L1
England and Wales; Part F, Part G and Part J
Section III Scotland; Part L and Part F Northern
Ireland.
Local water company bye-laws.
The Control of Pollution (Oil) Regulations.
OFTEC Standards.
Where no specific instruction is given, reference
should be made to the relevant codes of practice.
Installations in Eire (Republic of Ireland)
The Installation must be performed by a
competent and suitably trained person in
accordance with the following Eire regulations.
Current Building Regulations -
Republic of Ireland
ETCI rules for electrical installation
For further guidance see:
OFTEC Technical book three -
Regional requirements: Republic of Ireland

GENERAL INFORMATION
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
5
APPLIANCE
INFORMATION
GENERAL INFORMATION
STANDARD PACKAGE:
A - Floor standing oil fired condensing boiler for
open vent and sealed domestic central heating
and mains fed hot water.
B - Literature pack.
855mm
600mm
A
520mm
B
Check List
Hardware/Literature pack
Item Qty
Greenstar Heatslave Installation/Servicing Instructions........................1
Users Instructions ..........................................................................................1
Fascia Information Card.................................................................................1
Flue Trim ...........................................................................................................1
Top Panel Inset Plate......................................................................................1
Edge Clips .......................................................................................................1

TECHNICAL DATA INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
6
TECHNICAL DATA
Central Heating
Primary water capacity (total) litres
Available pump head (20°C difference) at max. output metres water
Max. permissible system operating pressure bar
in accordance with WRAS guidelines
Flow restrictor colour
Domestic Hot Water
Maximum flow rate (±15%) litres/min
Minimum inlet pressure (dynamic) for maximum flow rate bar
Maximum hot water temperature rise for 90 litres draw off (@max flow rate) °C
Flue
Exit flue gas mass flow kg/hr
Pipework connections
Fuel line (compression) mm
CH flow mm
CH return mm
Water main inlet mm
DHW outlet mm
CH drain hose connection
Condensate (polypropylene) mm
Electrical
Electrical power supply voltage AC...V
Frequency Hz
Max. power consumption W
Thermostats
CH control thermostat range (cut in/cut out) °C
DHW control thermostat range (cut in/cut out) °C
CH & DHW control thermostat differential °C
Boiler high limit thermostat set point °C
Boiler manual reset overheat thermostat set point °C
Flue reset overheat thermostat set point °C
Tank manual reset overheat thermostat set point °C
DHW pipe thermostat °C
General Data
Maximum hearth temperature °C
SEDBUK (Band A) %
Appliance protection rating (with programmer blanking plate fitted) IP
Appliance protection rating (with fascia programmer fitted) IP
Weight (excluding packaging) kg
DESCRIPTION UNITS 12/18 18/25 25/32
APPLIANCE
INFORMATION
69
4.7
2.5
Lime
15
1.5
40
29
10
22
22
15
22
21.5
230
50
240
55/81
55/80
5
92
105
110
98
70
<100
90.2
20
20
177
69
4.0
2.5
—
18
1.2
40
40
10
22
22
15
22
21.5
230
50
240
55/81
55/80
5
92
105
110
98
70
<100
90.1
20
20
177
72
4.2
2.5
—
22
0.9
40
51
10
28
28
15
22
21.5
230
50
263
55/81
55/80
5
92
105
110
98
70
<100
90.3
20
20
179

16
6789
11
13 14
4
2
17
43
39
45
37
44
38
42
15
1
18 19
20
28
27
29
i)
47
48
46
iii)
v)
21
ii)
iv)
a
3
5
10
30
31
32
41
40
23
24
25
26
33
35
36
34
12
22
LAYOUT & COMPONENTS
1 CONTROL BOX ASSEMBLY
2 CASING SIDE PANEL
3 FLUE 'KNOCK-OUT' SECTION
4 DIVERTER VALVE
5 AUTO AIR VENT
6 CH CONTROL & MANUAL RESET
OVERHEAT THERMOSTATS
7 CIRCULATING PUMP
8 HIGH LIMIT THERMOSTAT
(AUTOMATIC RESET)
9 PRESSURE RELIEF VALVE
10 PUMP AUTO AIR VENT ( Under
protective cap)
11 DHWFLOWSWITCH
12 DHW PIPE THERMOSTAT
13 DHW HEAT EXCHANGER
14 EXPANSION VESSEL
15 CASING SUPPORT PANEL
16 MANUAL RESET FLUE OVERHEAT
THERMOSTAT
17 CLIP FOR FIRE VALVE SENSOR
18 CLIP FOR POWER CABLE
19 AIR INLET PIPE & CASING
20 SECONDARY HEAT EXCHANGER
MANUAL AIR VENT
21 SECONDARYHEATEXCHANGERDRAIN
22 1” BSP
23 OIL ISOLATION VALVE
24 FLEXIBLE CONDENSATE OUTLET PIPE
25 SECONDARY HEAT EXCHANGER
26 PRIMARY HEAT EXCHANGER
27 CONDENSATE TRAP
28 CONDENSATE DRAIN PIPE WITH
PUSH FIT CONNECTOR
29 PRIMARY HEAT EXCHANGER DRAIN
COCK
30 TRAY
31 COMBUSTION CHAMBER ACCESSDOOR
32 HEATSLAVE TANK DRAIN COCK
33 HEATSLAVE TANK
34 FLUE MANIFOLD ACCESS COVER
35 FLUE GAS SAMPLING POINT
36 DATA LABEL
37 PRESSURE GAUGE
38 QUICK REFERENCE GUIDE SLOT
39 LOCK-OUT INDICATOR
40 MANUAL RESET TANK OVERHEAT
THERMOSTAT (behind plastic cover)
41 POWER ON INDICATOR
42 OVERHEAT RESET BUTTONS
43 LOCK-OUT RESET BUTTON
44 CH TEMPERATURE CONTROL
45 DHW TEMPERATURE CONTROL
46 RIELLO RDB 1 (12/18)
RIELLO RDB 2.2 (18/25, 25/32)
i) Control box
ii) Motor
iii) Air intake casing
iv) Oil pump
v) Combustion head
47 CLIP - AIR INTAKE HOSE
48 AIR INTAKE HOSE
OPTIONAL ACCESSORIES (not supplied)
a - 7 day TWIN CHANNEL DIGITAL
PROGRAMMER
Part No. 7 716 192 033 0
LAYOUT & COMPONENTS
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
7
APPLIANCE
INFORMATION
The diagram below excludes the top, front and RH side
casing panels.

CLEANING PRIMARY SYSTEMS
IMPORTANT: All the following Pre-Installation sections must be read and
requirements met before starting boiler or flue installation.
CAUTION: ISOLATE THE MAINS SUPPLIES BEFORE STARTING ANY WORK AND
OBSERVE ALL RELEVANT SAFETY PRECAUTIONS.
CLEANING PRIMARY SYSTEMS INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
8
PRE -
INSTALLATION
BEFORE CLEANING THE SYSTEM:
ENSURE THE SYSTEM AND PIPEWORK IS
IN GOOD WORKING ORDER.
FLUSH THE EXISTING SYSTEM WITH A
POWER FLUSHING MACHINE OR WITH A
CHEMICAL CLEANER BEFORE
INSTALLING NEW COMPONENTS.
CLEANING THE PRIMARY SYSTEM:
4Cleanse the system in accordance with
BS 7593.
4Fill the system with cold mains water to the
recommended pressure and check for leaks.
4Open all drain cocks and drain the system.
4Close drain cocks and add a suitable flushing
agent at the correct strength for the system
condition in accordance with the manufacturer's
instructions.
4Circulate the flushing agent before the boiler
is fired up.
4Run the boiler and system at normal operating
temperature in accordance with the
manufacturer's instructions.
4Drain and thoroughly flush the system to
remove the flushing agent and any debris.
IMPORTANT: 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
warranty.

MAINS SUPPLY
ELECTRIC SUPPLY:
• Supply: 230V - 50Hz.
• Cable: PVC insulated 0.75mm2(24 x
0.2mm) temperature rated to 90°C.
• Protection IP20.
• External 5A fuse to BS1362.
• The appliance must be earthed.
• Refer to IEE regulations for cross bonding
requirements.
• It must be possible to isolate the appliance
from the electrical supply with at least a 3mm
contact separation in both poles supplying
the appliance.
• Wiring between the appliance and the
electrical supply must comply with IEE wiring
regulations and any local regulations which
may apply for fixed wiring to a stationary
appliance.
• Any system connected to the boiler must not
have a separate electrical supply.
WATER SUPPLY:
The following are general requirements and if
necessary the advice of the local water company
should be sought before fitting the appliance.
• The appliance cold water supply should be
the first connection off the water main where
possible.
• Maximum mains fed water pressure 10 bar.
If necessary, fit a pressure reducing valve.
IMPORTANT: 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.
• Where the water main supply has a non-
return, back flow prevention valve fitted, a
mini expansion vessel (A) must be connected
to the mains water inlet pipe (B) between the
non-return valve (C) and the boiler (D) as
shown opposite.
Use in hard water areas:
Normally there is no need for water treatment to
prevent scale formation as the maximum
temperature of the heat exchanger is limited by
the electronic control circuit.
In areas where the temporary water hardness
exceeds 200ppm, 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.
MAINS SUPPLY
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
9
PRE -
INSTALLATION
12/18kW
Water Mains Pressure:
Minimum dynamic mains water pressure for
maximum performance.
1.5 bar 1.2 bar 0.9 bar
18/25kW 25/32kW
MAINS WATER EXPANSION VESSEL:
A - Mini expansion vessel, part No. 7 716 192 105
B - Mains water inlet
C - Non-return valve
D - Boiler
A
BC
D

OIL SUPPLY INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
10
PRE -
INSTALLATION
OIL SUPPLY
OIL SUPPLY :
•This appliance is suitable for kerosene (28
second oil) only, no other fuel must be used.
• Plastic or steel tanks should be installed to
BS 5410. A steel tank should conform to
BS 799: part 5 and have a slope of 1 in 24
away from the outlet valve with a sludge cock
at its lower end.
• Do not use galvanised steel tanks or
pipework for the oil supply system.
• Do not use soldered joints on the oil
supply pipework.
a) Single pipe gravity feed system:
The oil storage tank (A) must be positioned so
that the oil level does not exceed 4 metres above
the level of the burner oil pump (J) and in addi-
tion the oil level must be at least 300mm above
the oil pump (J). Where the maximum oil level in
the oil storage tank exceeds 4 metres, a head
breaking device must be installed between the
tank (A) and the burner oil pump (J).
b) Double pipe sub-gravity feed system:
Maximum suction height 3.5 metres. Non-return
valves must be fitted to the inlet and return oil line
between the oil pump (J) and oil storage tank (A).
AF
BN GJ
4m max.
K
a)
H
300mm min.
B DB C
MAXIMUM PIPE RUN FOR SINGLE PIPE GRAVITY FEED SYSTEM
B
A
DB
C
E
K
3.5m max.
L
L
b)
H
FG
B
150mm
MAXIMUM PIPE RUN FOR DOUBLE PIPE SUB-GRAVITY FEED SYSTEM
NJ
E
A - Oil storage tank.
B - Isolating valve.
C - Oil strainer & water separator.
D - Fire valve to BS 5410.
E - External wall.
F - Fire valve sensor.
G - Oil burner.
H - Oil supply pipe.
J - Oil pump.
K - Full base (plastic tanks).
L - Non-return valve.
M - De-aerator.
N - Oil filter (70μmmax filtration size)
NOTE: All dimensions are in metres unless stated otherwise.
The maximum pipe run figures are based on using copper pipe with an inside diameter of
2mm less than the Ø.
HEAD 10mmØ 12mmØ
0.5 12 30
1.0 25 69
1.5 37 91
2.0 49 100
HEAD 10mmØ 12mmØ
2.5 62 100
3.0 74 100
3.5 87 100
4.0 99 100
HEAD 10mmØ 12mmØ
050 100
0.5 44 100
1.0 38 95
1.5 32 80
HEAD 10mmØ 12mmØ
2.0 26 66
2.5 20 50
3.0 14 37
3.5 8 22

B
A
M
B
F
C
G
J
E
D
c)
MAXIMUM PIPE RUN FOR SINGLE PIPE SUCTION LIFT WITH DE-AERATOR
H
FUEL FLOW RATE FUEL FLOW RATE
K
3.5m max.
H
P
R
S
T
P
N
OIL SUPPLY
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
6 720 802 432 issue A 04/2012
11
PRE -
INSTALLATION
OIL SUPPLY
c) Single pipe suction lift with de-aerator
Maximum suction height 3.5 metres. The oil
tank (A) must be positioned below the oil pump
(J). Create an inlet and return loop between the
de-aerator (M) and oil pump (J).
A non-return valve must be incorporated within
the de-aerator or fitted to the oil line between
the oil storage tank (A) and the de-aerator (M).
A top feed oil tank fitted with a de-aerator
using an internal non-return valve should have
any non-return valves fitted in the base of the
tank to the suction line removed to assist
purging air from the oil line.
Pipework
4Use copper pipe of the correct diameter
according to the information shown opposite.
• If using soft copper pipe (R220) with a
compression fitting, an insert must be used
to prevent the pipe from collapsing or
distorting when the fitting is tightened.
4Slide nut (P) and olive (R) onto the oil
supply pipe (H).
4Slide insert (S) into the pipe.
4Offer the pipe to the fitting (T) and tighten the
nut (P).
4Use flexible hoses to connect to the oil pump (J).
4Lay the oil supply pipe (H) as straight and
level as possible to avoid air pockets and
unnecessary friction losses. Route away
from the boiler access door or other hot
surfaces.
4Install a manual isolating valve (B) to the oil
supply pipe (H), as close to the oil storage
tank (A) as possible.
4Fit an oil strainer and water separator (C) to
the oil supply pipe, near the oil storage tank.
Fit an additional oil filter (N, 70μmmax
filtration size) close to the boiler, but not
inside the boiler casing.
4Fit a fire valve in accordance with BS 5410.
The fire valve (D) should be fitted externally
to the building with the fire valve sensor (F)
located within the appliance case.
A fire valve with a shut off temperature of
85°C or higher must be fitted to avoid
the possibility of nuisance shut offs.
A capillary type valve provides a neat and
simple installation. Alternatively, a fusible
link or electrical system may be used.
Under no circumstances should a
combination isolating/fire valve be used
as the sole fire protection device.
HEAD 2.5kg/h 5kg/h 10kg/h 10kg/h
8mmØ 8mmØ 8mmØ 10mmØ
0 100 55 26 100
0.5 95 4523100
1.0 80 40 20 90
1.5 70 35 17 75
HEAD 2.5kg/h 5kg/h 10kg/h 10kg/h
8mmØ 8mmØ 8mmØ 10mmØ
2.0 60 30 14 65
2.5 45 25 11 50
3.0 35 15 8 35
3.5 25 10 5 20
The table and illustration above is a guide only and does not in any way override the
de-aerator manufacturers instructions.

D
R R
R R
B
P
D
C
TLTL
TL LL
A
U
E
WATER SYSTEMS & PIPEWORK
PRIMARY SYSTEM PLASTIC PIPEWORK:
• Any plastic pipework used for the CH system
must have a polymeric barrier, complying with
BS 7921 and installed to BS 5955 with
1000mm (minimum) length of copper or steel
pipe 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 approx. 50°C
with 1000mm (minimum) length of copper or
steel pipe connected to the boiler, and a 20k
differential must be maintained at the
appliance.
PRIMARY SYSTEM/CONNECTIONS/VALVES:
• Do not use galvanised pipes or radiators.
• All system connections, taps and mixing
valves must be capable of sustaining a
pressure of 3 bar.
• Radiator valves should conform to
BS 2767:10.
• All other valves should conform to BS 1010.
• On new installations TRVs must be used on
all radiators except the radiator where the
room thermostat is sited, this must be fitted
with lockshield valves and left open. All
installations should have TRVs fitted to
radiators within the sleeping accommodation.
• An automatic bypass valve must be connected
between the heating flow and return pipes
where TRVs are used on radiators. This must
be fitted to give at least a 3m circuit when
activated.
• Drain cocks are required at all the lowest
points on the system.
• Air vents are required at all high points on the
system.
SEALED PRIMARY SYSTEM:
• Where the system volume is more than 180
litres at 0.5 bar or exceeds 2.65 bar at
maximum heating temperature an extra
expansion vessel (B) must be fitted as close
as possible to the appliance in the central
heating return.
• Pressurise the extra expansion vessel (B) to
the same figure as the expansion vessel (A)
built into the appliance.
A - Appliance expansion vessel
B - Extra expansion vessel
C - Automatic bypass valve
D - Drain cock
E - Appliance
L - Lockshield valve
P - Pressure relief discharge
R - Radiators
T - TRV
TYPICAL SEALED SYSTEM
IMPORTANT: The boiler should not be
allowed to operate with a return
temperature of less than 40°C when
the system is up to operating temperature.
WATER SYSTEMS & PIPEWORK INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
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IMPORTANT:
The Greenstar Heatslave boiler is for use
with sealed central heating systems only.

WATER SYSTEMS & PIPEWORK
FILLING PRIMARY SEALED SYSTEMS:
• Filling the system must comply with one of the
methods shown opposite.
• The filling point must be at low level and must
never be a permanent direct fixing to the
mains water supply.
• Filling links must be WRAS approved.
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-siphon device must be fitted to the
shower hose.
Only thermostatically controlled showers are
suitable for use with this appliance.
• Bidets with direct hot & cold mains water can
be used (with the approval of the local water
authority) and must be the over rim flushing
type with shrouded outlets to prevent the
fitting of hand held sprays.
DOMESTIC HOT WATER:
• Taps and mixing valves must be capable of
sustaining a pressure up to 10 bar in
accordance with the Water Regulations as
they will be operating at mains water pressure.
• Hot water temperature and flow rate are
affected by the size and insulation of pipework
making up the distribution system and are
controlled by the hot water tap and the water
main inlet pressure. A mixing valve can be fitted
if a more permanent setting is required.
• If using more than one outlet at once causes
water flow starvation, fit flow balancing valves
or Ball-O-Fix valves to the appropriate outlets.
Plastic pipework
• Any plastic pipework used for the DHW
system must have a polymeric barrier,
complying with BS 7921 and installed to
BS 5955 with 1000mm (minimum) length
of copper or steel pipe connected to the boiler.
• Before installing plastic pipework, the pipe
manufacturer’s literature should be consulted.
• To prevent the temperature & pressure
exceeding the limits advised by the pipe
manufacturer, a pressure reducing valve should
be used to prevent the incoming water
pressure exceeding 3 bar (maximum). Also a
mini expansion vessel must be fitted to absorb
the expanding water.
• When selecting plastic pipework for use with
domestic water supply, it should be ensured that
it is compliant with all current local & national
legislation & regulations, including building
regulations part G, BS 7291 - 1,2 & 3: 2006,
BS 8000 - 15-15: 1990 and information.
Heating return
Hose
return
Non return
valve
Non return
valve
Test cock
Stop
cock
Water main
supply
Stop
cock
Temporary hose
Greenstar Heatslave
oil fired combination boiler
Hot water supply
to property
Mini expansion
vessel
0.75Ltr capacity
Balanced cold water
supply to property
3 bar pressure
reducing
valve
MCW
Check valve/
non return valve
Incoming mains
stop valve
WATER SYSTEMS & PIPEWORK
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
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CONDENSATE PIPEWORK
INTERNAL CONNECTION
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CONDENSATE PIPEWORK
INTERNAL CONNECTION
Key to diagrams:
1. Condensate dischange from boiler
2. Universal connector
3. Soil and vent stack
4. Minimum 450mm and up to three storeys
5. Visible air break at plug hole
6. Sink or basin with integrated overflow
7. 75mm sink waste trap
8. Condensate pump
CONDENSATE PIPEWORK:
• 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 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.
Internal connections:
• In order to minimise risk of freezing during prolonged
cold spells, the following methods of installing a
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.
• Alternatively if the first option is not possible an
internal kitchen or bathroom waste pipe, washing
machine waste pipe etc. can be used.
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.

CONDENSATE PIPEWORK
EXTERNAL CONNECTION
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CONDENSATE PIPEWORK
EXTERNAL CONNECTION
Key to diagrams continued:
9. Pipe work transition
10. Insulate and increase pipe size
11. External rain water pipe into foul water
12. External air break
13. Air gap
14. PVCu starp on fitting
15. 43mm 90° male/female bend
CONDENSATE PIPEWORK RUN EXTERNALLY:
• Pipe work length should be kept to a minimum and
the route as vertical as possible.
• Weather proof insulation must be used.
• Care should be taken when siting a soakaway to
avoid obstructing existing services.
• 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.
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:
4The external run be kept as short as possible and
not exceed three metres.
4The 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.
4The pipe should be insulated using suitable
waterproof and weather resistant insulation.
4The external pipe should take the shortest and least
exposed 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.
4The 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 brake:
• 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.
NOTE: 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.

CONDENSATE TO SOAK AWAY &
PRESSURE RELIEF PIPEWORK
Key to diagrams continued:
16. 100mm Ø minimum plastic pipe
17. Drainage holes
18. Limestone chippings
19. Bottom of sealed tubed
CONDENSATE SOAK AWAY:
• All national and, where appropriate, local
regulations for the discharge and neutralisation of
condensate should be followed.
• 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.
NOTE: Minimum hole size for the condensate soak
away must be 400mm deep by 300mmØ .
• In situations where there are likely to be extremes of
temperature or exposure, the use of a proprietary
trace heating system 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.
NOTE: Internal pipe runs in unheated areas such
as lofts, basements and garages should
be treated as external runs.
Making it safe:
• Condensate pipework must not leak, freeze or
block up.
• Condensate traps must be filled before starting
up the boiler to prevent potentially harmful flue
products escaping via the condensate route.
• Do not dispose of condensate into water
recovery systems.
PRESSURE RELIEF PIPEWORK:
• 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.
3 - Outside wall.
1_3 Drain pipe.
4 - External drain.
CONDENSATE TO SOAK AWAY &
PRESSURE RELIEF PIPEWORK
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
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UNSUITABLE FOR CLAY SOIL TYPES

• This boiler is only suitable for installing
internally within a property at a suitable
location onto a fixed rigid surface of the same
size as the boiler and capable of supporting
the boiler weight.
• The boiler must be installed on a flat level
surface to ensure condensate does not enter
the primary heat exchanger.
• The boiler is not suitable for external
installation unless a suitable enclosure is
provided.
• Roof space installations must fully conform to
BS 5410 part 1 section 4.6.9.
Open flue model (CF):
• In order to ensure clean and efficient
combustion an adequate supply of air must
be delivered to the combustion chamber.
• To provide sufficient air a suitable inlet must
be provided into the room or space in which
the boiler is situated.
An air brick or other form of continuous air
supply may have to be built into the installation
in order to ensure an adequate supply of air.
• If the appliance is to be installed in a confined
space or compartment two air vents are
required, one at high level and one at low level.
The minimum free area of each vent is
shown opposite and depends whether the
air is taken from another room or from
outside the building.
• Where the air is taken from another room that
room must contain an air inlet as described
above.
Room sealed balanced flue model (RS):
The appliance does not require a separate vent
for combustion air.
• Installation in cupboards or compartments
require permanent vents for cooling purposes,
one at high level and one at low level, either
direct to outside air or to a room.
• Both vents must pass to the same room or be
on the same wall to the outside air.
The minimum air vent free area is given in the
table opposite.
a: INSTALLATION CLEARANCES:
Diagram (a) shows the minimum space
recommended to install the boiler only.
b: SERVICE CLEARANCES:
Diagram (b) shows the minimum space
required to carry out an annual service.
c: MAINTENANCE & REPAIR CLEARANCES:
The appliance is suitable for an under worktop
installation providing that the worktop above the
boiler (min 10mm clearance) is removable for
maintenance and repair and the front of the
boiler is not enclosed.
* Remove the flue 'knock-out' panel sections if
this clearance is less than 75mm.
** Due to changes to BS 5410 and modern
building design, these figures no longer
incorporate the adventitious ventilation allowance.
600mm
300mm
100mm
100mm
720mm
1200mm
1155mm
a: RECOMMENDED
INSTALLATION CLEARANCES
b: ANNUAL SERVICE CLEARANCES
600mm
10mm
5mm*
5mm*
530mm
1200mm
865mm
c: MAINTENANCE & REPAIR CLEARANCES
600mm
300mm
5mm*
5mm*
530mm
1200mm
1155mm
MINIMUM AIR VENT AREA (cm2) FOR APPLIANCES INSTALLED IN A COMPARTMENT:
1Internal air to and from a space/room inside the building. 2External air to and from directly outside the building.
12/18kW
CF minimum air inlet sizes**
99 138 176
18/25kW 25/32kW
Output
Size cm2
BOILER LOCATION &
CLEARANCES
Conventional flue
kW
Internal1ventilation External2ventilation
High
Level Low Level High Level Low Level
12/18 198 279 99 198
18/25 275 413 138 275
25/32 352 528 176 352
Room Sealed flue:
kW
Internal1ventilation External2ventilation
High
Level Low Level High Level Low Level
12/18 198 198 99 99
18/25 275 275 138 138
25/32 352 352 176 176
BOILER LOCATION &
CLEARANCES
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600mm
2250mm
600mm
2250mm
600mm
600mm radius
750mm
750mm
2250mm
m
2250m
COMPARTMENTS:
Follow the requirements of BS 5410 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 (if perforated,
maximum hole sizes of 13mm) to separate
the boiler from the airing space.
Venting compartments:
There must be sufficient clearance around the
appliance to allow proper circulation of
ventilation air. The clearances required for
installation and servicing will normally be
adequate for ventilation.
• Ventilation must be provided for boilers
fitted into compartments as described in
B S 5410.
• Combustion air must not be taken from a
room or internal space containing a bath or
shower and must not communicate with a
protected area such as a hall, stairway,
landing, corridor, lobby, shaft etc.
• Air vents must allow access for clean free
air and must be sited to comply with the flue
terminal position requirements.
• Air ducting runs must not exceed 3m.
• Low level air vents must be less than
450mm from the floor.
• A warning label must be added to the vents
with a statement to the effect: ''Do not block
this vent. Do not use for storage.”
SHOWER / BATHROOMS:
The boiler must not be installed in zones 0, 1
or 2 (the shaded areas shown on the diagrams oppo-
site).
IMPORTANT: conventional flued boilers
must not be fitted in a bathroom.
IMPORTANT: any appliance control using
mains electricity must not be able to be
touched by a person using the bath or
shower.
Electrical switches, fused spur and socket
outlets must not be fitted in the bath-
room.
In all cases the IEE wiring regulations
must be consulted.
All pipework in bathrooms and shower
rooms must be cross bonded.
BOILER LOCATION &
CLEARANCES
1
212
0
1
212
0
BOILER LOCATION & CLEARANCES INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE 12/18-18/25-25/32
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FLUE TERMINAL POSITIONS
• Flue terminals must be positioned to avoid
combustion products entering into buildings.
• The flue must be fitted and terminated in
accordance with the recommendations of
B S 5410.
• The flue must not cause an obstruction.
• Discharge from the flue outlet must not be a
nuisance.
• Flue gases have a tendency to plume and in
certain weather conditions a white plume of
condensation will be discharged from the flue
outlet which could be regarded as a
nuisance, for example, near security lighting.
• There should be no restriction preventing the
clearance of combustion products from the
terminal.
• The air inlet/outlet duct and the terminal of
the boiler must not be closer than 25mm to
any combustible material. Detailed
recommendations on protection of
combustible materials are given in BS 5410:1
• A protective terminal guard must be fitted if
the terminal is 2m or less above a surface
where people have access.
The guard must be spaced equally (minimum
50mm) around the flue and fixed to the wall
with plated screws.
Stainless steel terminal guard.
Part No: 7 716 190 050
The following additional guidelines (from part
L Exceptions Guidance Document) are
recommended when determining the flue
outlet position:
• Avoid discharging flue gases into car ports
or narrow passageways.
• *Minimum distance of the flue terminal from
above ground is 2100mm where directed to a
public footpath, private access route or a
frequently used area and 2500mm from a
car parking area.
• **Minimum distance of the flue terminal to a
facing wall, fence, building or property
boundary is 2500mm.
O
P
boundary
F
J
H
B
A
G
E
M
C, D
N
F
F
K
L
boundary
Q
Q
Q
R
Q
Q
Q
Q
Pitched roof
Flat roof
Key: — Not applicable, N/A Not allowed, CF Conventional flue, RS(H) Room Sealed Horizontal flue,
RS(V) Room Sealed Vertical flue.
Notes:
1. Terminals should be positioned so as to avoid products of combustion accumulating in stagnant pockets around the building or
entering into buildings.
2. Vertical structure in N, O and P includes tank or lift rooms, parapets, dormers etc.
3. Terminating positions should be at least 1.8m from an oil storage tank unless a wall with at least 30 min fire resistance and
extending 300mm higher and wider than the tank is provided between the tank and the terminating position.
4. Where a flue is terminated less than 600mm away from a projection above it and the projection consists of plastics or has a
combustible or painted surface, then a heat shield of at least 750mm wide should be fitted.
5. If the lowest part of the terminal is less than 2m above the ground, balcony, flat roof or other place to which any person has
access, the terminal should be protected by a guard.
6. Notwithstanding the dimensions given above, a terminal should not be sited closer than 300mm to combustible material. In the
case of a thatched roof, double this separation distance should be provided. It is also advisable to treat the thatch with a fire
retardant material and close wire in the vicinity of the flue.
7. It is essential that a flue or chimney does not pass through the roof within the shaded area delineated by dimensions Q and R.
8. Where protection is provided for plastic components, such as guttering, it is essential that this is to the standard specified by the
manufacturer of the plastic components.
TERMINAL POSITION CF RS(H) RS(V)
A1 4 Directly below an opening, air brick, opening window, etc N/A 600mm N/A
B1 4 Horizontally to an opening, air brick, opening window, etc N/A 600mm N/A
C8Below a plastic/painted gutter, drainage pipe or eaves if
combustible material protected
N/A 75mm N/A
D8Below a plastic/painted gutter, drainage pipe or eaves
without protection to combustible material
N/A 600mm N/A
EFrom vertical sanitary pipework N/A 300mm N/A
F 3From an external or internal corner or from a surface or
boundary alongside the terminal
N/A 300mm N/A
G5Above ground or balcony level N/A 300mm* N/A
H3From a surface or boundary facing the terminal N/A 600mm** N/A
JFrom a terminal facing the terminal — 1200**mm —
KVertically from a terminal on the same wall N/A 1500mm N/A
LHorizontally from a terminal on the same wall —750mm —
MAbove the point of highest intersection with the roof 600mm — 600mm
N2From a vertical structure on the side of the terminal 750mm —750mm
O2Above a vertical structure less than 750mm from the side of the
terminal
600mm —600mm
P2 From a ridge terminal to a vertical structure on the roof 1500mm —N/A
QAbove or to the side of any opening on a flat or sloping roof 300mm — 300mm
RBelow any opening on a sloping roof 1000mm —1000mm
Minimum dimension of the flue terminal position for oil fired appliances:
FLUE TERMINAL POSITIONS
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CONVENTIONAL FLUE
C
B
A
D
E
A - Boiler
B - Flue
C - Max. 2 bends at 135°
D - Anti down-draught terminal
E - Chimney
• Open (conventional) flued appliances must
not be installed in a bedroom, bathroom or
bedsitting room.
• The flue system must be in accordance with
BS 5410 : Part 1 and the current Building
Regulations.
• The flue must be constructed of materials
suitable for use with condensing combustion
products.
• External flue systems must be of the insulated
type.
• Brick and masonry chimneys must be lined
with a suitable non-combustible material and
properly jointed to withstand the effects of
the working temperature (minimum rating of
material 120°C) of the appliance and any
condensate which may form.
• All flue joints must be sealed to prevent the
leakage of condensate and combustion
products.
• Ensure that joints are made so that the
condensate runs away and is not collected
within the joint.
NOTE: The flue can be increased in size from
the boiler take off point providing the joint is
correctly sealed. Never reduce the flue diameter
from the boiler take off point.
CF Sizing:
• 12/18 and 18/25 = 100/103mmØ
25/32 = 130mmØ*
*Unless installing Worcester Greenstar
Oilfit Conventional 100mmØ Flexible flue.
• Because the flue operates at a lower
temperature on a condensing boiler
compared to that of a conventional
appliance, the flue draught will be lower.
Typically the draught will be between
0.5mmwg and 4.4mmwg, measured with the
flue warm but the burner not firing. The actual
figure will vary depending on weather
conditions, flue height and position.
• The flue should be vertical and contain as few
bends as possible, a maximum of two 135°
bends should be used.
• The flue outlet must be extended beyond the
eaves of the building and where possible,
above the apex.
• Fit a suitable anti down-draught terminal
where down draughts are experienced.
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