7.2.2Selector switch in the hot water only position27
7.2.3Selector switch in the heating & hot water position27
7.2.4Appliance functions27
7.2.5Heating mode27
7.2.6DHW mode28
7.3Checking and adjusting burner pressure28
7.3.1Setting the maximum burner pressure28
7.3.2Setting the minimum burner pressure28
7.4Combustion analysis test28
7.5Checking the expansion vessel29
7.6External faults29
7.6.1Installation faults29
7.7Electrical checks29
7.7.1Earth continuity test29
7.7.2Short circuit test29
7.7.3Polarity check29
7.7.4Reversed polarity or supply fault29
7.7.5Resistance to earth check30
7.8Fault finding30
7.9Fault codes31-38
Wiring diagramsPage
8.1External wiring39
8.2Typical control applications39
8.3Vokera time clock39
8.4Vokera remote control39
8.5Vokera room thermostat39
8.6Other controls39
Exploded diagramsPage
Table 1 - 543 - 48
L.P .G. instructionsPage
10.1Related documents49
10.2Technical data49
10.3Converting the appliance gas type49
10.4Gas supply49
10.5Gas supply installation49
10.6Checking and adjusting burner pressure49
10.6.1Setting the maximum burner pressure49
10.6.2Setting the minimum burner pressure49
INTRODUCTION
The Syntesi range of appliances is comprised of 3 models
of high-efficiency combination boiler with outputs to
heating & DHW of 24, 28, & 34kW respectively. Each
appliance – by design – incorporates electronic ignition,
circulating pump, expansion vessel, safety valve, pressure
gauge, and automatic by-pass.
The Syntesi range is produced as room sealed, category
II2H3+ appliances, suitable for internal wall mounting
applications only . They are provided with a fan powered
flue outlet with an annular co-axial combustion air intake
14
9
8
7
10
3
11
6
5
4
2
1
12
272830 312932
13
that can be rotated – horizontally – through 360 degrees
for various horizontal or vertical applications. The Syntesi
range can also be used with the Vokera twin flue system.
The Syntesi range is approved for use with C12 & C32
type flue applications.
These appliances are designed for use with a sealed
system only; consequently they are not intended for use
on open vented systems.
10Latent Heat Collector
11Condense Sensor
12Flue Gas Analysis Test Point
13Flue Outlet
14Air Intake
15Differential Analog Pressure Switch
20
16Silicone Pressure T ube
17Silicone Negative Pressure T ube
21
18Fan Assembly
19Combustion Chamber
22
23
20Burner Temperature Control
21Expansion Vessel
22Transformer
24
23Gas V alve
24Modulator Coil
25
25Condense Trap
26Domestic Hot Water Flow Switch
26
27Hot Water Temperature Control
28Mode Selector Switch
29Status LED
30Temperature Indicator
31DHW Request LED
32Central Heating Temperature Control
33Combustion Switch
34Timeclock Aperture (optional)
35Pressure Gauge
Fig. 1
353433
1
SECTION 1DESIGN PRINCIPLES AND OPERATING SEQUENCE
1.1PRINCIPLE COMPONENTS
● A fully integrated electronic control board
featuring electronic temperature control, anticycle control, pump over-run, self-diagnostic
fault indicator, full air/gas modulation.
● Low-water-content, copper heat exchanger.
● Electronic ignition with flame supervision
● Integral high-head pump
● Fan
● Expansion vessel
● Analogue pressure switch (P AD)
● Water pressure switch
● Two-stage gas valve
● Pressure gauge
● Safety valve
1.2MODE OF OPERATION (at rest)
When the appliance is at rest and there are no
requests for heating or DHW, the following functions are active:
● pre-heat function – the pre-heat function ena-
bles the appliance to periodically light and maintain the temperature of the DHW heat exchanger. This “keep-hot” facility enables the
appliance to provide an instantaneous response to DHW requests.
● 2-stage frost-protection system – the frost-pro-
tection system protects the appliance against
the risk of frost damage. The first stage enables activation of the pump should the temperature of the appliance fall to 7°C. The second
stage becomes active when the temperature
has dropped to 3°C. Should the second stage
become active, the appliance will function on
minimum power until it reaches 30°C.
● anti-block function – the anti-block function ena-
bles the pump and divertor valve actuator, to
be energised for short periods, when the appliance has been inactive for more than 19hours.
1.3MODE OF OPERA TION (Heating)
When there is a request for heat via the
programmer/time clock and/or any external
control, the pump and fan are started, the fan
speed will modulate until the correct signal
voltage is received at the control PCB. At this
point an ignition sequence is enabled.
Ignition is sensed by the electronic circuitry to
ensure flame stability at the burner. Once
successful ignition has been achieved, the
electronic circuitry increases the gas rate to 75%
for a period of 15 minutes. Thereafter, the boiler’s
output will either be increase to maximum or
modulate to suit the set requirement. When the
appliance reaches the desired temperature the
burner will shut down and the boiler will perform
a three-minute anti-cycle (timer delay).
When the request for heat has been satisfied the
appliance pump and fan may continue to operate
to dissipate any residual heat within the
appliance.
1.4MODE OF OPERATION (DHW)
When there is a request for DHW via a hot water
outlet or tap, the pump and fan are started, the
fan speed will modulate until the correct signal
voltage is received at the control PCB. At this
point an ignition sequence is enabled.
During DHW request LED (31, fig. 1) is ON.
Ignition is sensed by the electronic circuitry to
ensure flame stability at the burner. Once
successful ignition has been achieved, the
electronic circuitry increases the gas rate to
maximum or will modulate output to stabilise the
temperature. In the event of the appliance
exceeding the desired temperature the burner will
shut down until the temperature drops.
When the request for DHW has been satisfied
the appliance pump and fan may continue to
operate to dissipate any residual heat within the
appliance.
1.5SAFETY DEVICES
When the appliance is in use, safe operation is
ensured by:
● a water pressure switch that monitors system
water pressure and will de-activate the pump,
fan and burner should the system water
pressure drop below the rated tolerance.
● a high limit thermostat that over-rides the
temperature control circuit to prevent or
interrupt the operation of the burner.
● an analogue pressure switch (PAD) that
checks the operation of the fan and flue thereby
allowing safe operation of the burner.
● a sensor that interrupts the operation of the
appliance if the condense pipe becomes
blocked.
● a safety valve which releases excess pressure
from the primary circuit.
1.6OPTIONAL ACCESSORIES
The Syntesi is suitable for use with a range of
optional accessories that enable enhanced
operation and/or applications. These include:
● RC05 remote control – the RC05 remote
control enables the appliance to be controlled,
adjusted, and monitored from another location
or room. The RC05 can also be used as a room
thermostat or programmable room thermostat.
● external sensor – used in conjunction with the
RC05 the external sensor enables the
appliance to automatically adjust its outlet flow
temperature in response to the outside
Expansion
vessel
AARV
Pump
Fig. 2
temperature.
Flue Outlet
Latent Heat
Collector
Diverter
Valve Motor
Pressure
Switch
ABCD
Air Intake
PAD
Main Heat
Exchanger
Main
Burner
Gas Valve
Domestic
Heat
Exchanger
DHW Flow
Switch
2
SECTION 2TECHNICAL DATA
2.1 Central heatingSyntesi 25Syntesi 29Syntesi 35
Heat input25.0 kW29.0 kW35.0 kW
Max heat output 60/80°C (return & flow temp.)24.1 kW28.0 kW33.9 kW
Max heat output 30/50°C (return & flow temp.)25.9 kW29.7 kW36.2 kW
Min heat output 60/80°C (return & flow temp.)9.5 kW9.5 kW 9.4 kW
Min heat output 30/50°C (return & flow temp.)10.1 kW10.2 kW 10.2 kW
Minimum working pressure0.45 bar
Maximum working pressure3.0 bar
Minimum flow rate350 l/h
2.2 Domestic hot water
Maximum input25.0 kW29.0 kW35.0 kW
Maximum output24.1 kW28.0 kW33.9 kW
Minimum output9.5 kW9.5 kW9.4 kW
Flow rate (35oC rise)9.9 kW11.5 kW13.9 kW
Maximum inlet pressure 6.0 bar
Minimum inlet pressure0.15 bar
Minimum flow rate 2.0 l/min
2.3 Gas pressures
Inlet pressure (G20) 20.0 mbar
Burner pressure maximum8.8 mbar9.3 mbar10.1 mbar
Burner pressure minimum1.5 mbar1.25 mbar1.00 mbar
Maximum gas rate2.65 Sm3/h3.07 Sm3/h3.75 Sm3/h
Minimum gas rate1.05 Sm3/h1.05 Sm3/h1.05 Sm3/h
Injector size (quantity)12 x 1.35 mm14 x 1.35 mm16 x 1.35 mm
2.4 Expansion vessel
Capacity 8-litres10-litres
Maximum system volume 76-litres91-litres
Pre-charge pressure 1.0 bar
Voltage (V/Hz)230/50
Power consumption 174W174W194W
Internal fuse2A
External fuse3A
2.9 Flue details (concentric)
Maximum horizontal flue length (60/100mm)5.75m4.90m0.75m
Maximum vertical flue length (60/100mm)6.55m5.70m1.55m
Maximum horizontal flue length (80/125mm)13.80m11.80m6.75m
Maximum vertical flue length (80/125mm)15.30m13.30m8.25m
2.9A Flue Details (twin pipes)
Maximum horizontal flue length (80mm + 80mm)25m+25m20m+20m10m+10m
Maximum vertical flue length (80mm + 80mm)25m+25m20m+20m10m+10m
2.10 Efficiency
SEDBUK (%)87.487.588.1
3
SECTION 2TECHNICAL DATA
2.1 1PUMP DUTY
Fig. 3 shows the flow-rate available – after allowing for pressure loss through the
appliance – for system requirements.
When using this graph, apply only the
pressure loss of the system. The graph
is based on a 20°C temperature differential.
Fig. 3
7
6,5
6
5,5
5
4,5
4
3,5
3
2,5
2
1,5
1
Water pressure (mbar)
0,5
0
0100200300400500600 700800900 1000 1100 1200 1300
S
y
n
te
s
Syntesi 35
i 2
5
&
2
9
Litres Per Hour
2.12 Emissions
Appliance
Syntesi 25Syntesi 29
Syntesi 35
NOx max/min160/140180/120160/110
CO max/min70/20100/6090/80
CO2 max/min6.5/4.86.60/4.156.5/3.7
CO/CO2 ratio max/min0.00108 to 1/0.00044 to 10.00152 to 1/0.00145 to 1 0.00138 to 1/0.00216 to 1
Fig. 4
H
H
KeyLocationMinimum distance
ABelow an opening (window, air-brik, etc.)300 mm
BAbove an opening (window, air-brik, etc.)300 mm
CTo the side of an opening (window, air-brik, etc.)300 mm
DBelow gutter, drain-pipe, etc.75 mm
EBelow eaves200 mm
FBelow balcony, car-port roof, etc.200 mm
GTo the side of a soil/drain-pipe, etc.150 mm
HFrom internal/external corner or boundary300 mm
IAbove ground, roof, or balcony level300 mm
JFrom a surface or boundary facing the terminal600 mm
KFrom a terminal facing a terminal1200 mm
LFrom an opening in the car-port into the building1200 mm
MVertically from a terminal on the same wall1500 mm
NHorizontally from a terminal on the same wall300 mm
PFrom a structure to the side of the vertical terminal300 mm
QFrom the top of the vertical terminal to the roof flashingAs determined by the fixed collar
of the vertical terminal
4
SECTION 3GENERAL REQUIREMENTS (UK)
This appliance must be installed by a competent
person in accordance with the Gas Safety
(Installation & Use) Regulations.
3.1RELATED DOCUMENTS
The installation of this boiler must be in
accordance with the relevant requirements of the
Gas Safety (Installation & Use) Regulations, the
local building regulations, the current I.E.E. wiring
regulations, the bylaws of the local water
undertaking, the Building Standards (Scotland)
Regulation, and Building Standards (Northern
Ireland) Regulations.
It should be in accordance also with any relevant
requirements of the local authority and the
relevant recommendations of the following British
Standard Codes of Practice.
3.2LOCATION OF APPLIANCE
The appliance may be installed in any room or
internal space, although particular attention is
drawn to the requirements of the current I.E.E.
wiring regulations, and in Scotland, the electrical
provisions of the Building Regulations, with respect
to the installation of the appliance in a room or
internal space containing a bath or shower.
3.3GAS SUPPL Y
The gas meter – as supplied by the gas supplier
– must be checked to ensure that it is of adequate
size to deal with the maximum rated input of all
the appliances that it serves. Installation pipes
must be fitted in accordance with BS 6891.
Pipe work from the meter to the appliance must
be of adequate size. Pipes of a smaller size than
the appliance gas inlet connection must not be
used. The installation must be tested for
soundness in accordance with BS6891.
If the gas supply serves more than one appliance,
it must be ensured that an adequate supply is
maintained to each appliance when they are in
use at the same time.
3.4FLUE SYSTEM
The terminal should be located where the
dispersal of combustion products is not impeded
and with due regard for the damage and
discoloration that may occur to building products
located nearby . The terminal must not be located
in a place where it is likely to cause a nuisance
(see fig. 4).
BS 5440P ART 1FLUES
BS 5440P ART 2FLUES & VENTILA TION
BS 5449P ART 1FORCED CIRCULA TION HOT W ATER SYSTEMS
BS 5546INSTALLATION OF GAS HOT WATER SUPPLIES FOR DOMESTIC PURPOSES
(2nd FAMILY GASES)
BS 6798INSTALLATION OF BOILERS OF RATED INPUT NOT EXCEEDING 60kW
BS 6891LOW PRESSURE INSTALLATION PIPES
BS 7074P AR T 1APPLICA TION, SELECTION AND INSTALLTION OF EXPANSION VESSELS AND
ANCILLARY EQUIPMENT FOR SEALED WATER SYSTEMS
When an appliance is installed in a room or internal
space containing a bath or shower, the appliance
or any control pertaining to it must not be within
reach of a person using the bath or shower.
The location chosen for the appliance must permit the provision of a safe and satisfactory flue
and termination. The location must also permit
an adequate air supply for combustion purposes
and an adequate space for servicing and air circulation around the appliance. Where the installation of the appliance will be in an unusual location special procedures may be necessary, BS
6798 gives detailed guidance on this aspect. A
compartment used to enclose the appliance must
be designed and constructed specifically for this
purpose. An existing compartment/cupboard may
be utilised provided that it is modified to suit.
Details of essential features of compartment/cupboard design including airing cupboard installations are given in BS 6798. This appliance is not
suitable for external installation.
3.4FLUE SYSTEM (Cont’d.)
In cold and/or humid weather, water vapour will
condense on leaving the terminal; the effect of
such pluming must be considered.
If installed less than 2m above a pavement or
platform to which people have access (including
balconies or flat roofs) the terminal must be
protected by a guard of durable material. The
guard must be fitted centrally over the terminal.
Refer to BS 5440 Part 1, when the terminal is
0.5 metres (or less) below plastic guttering or 1
metre (or less) below painted eaves.
3.5AIR SUPPL Y
The following notes are intended for general
guidance only .
This appliance is a room-sealed, fan-flued boiler,
consequently it does not require a permanent
air vent for combustion air supply . When installed
in a cupboard or compartment, ventilation for
cooling purposes is also not required.
5
3.6WATER CIRCULATION
Detailed recommendations are given in BS 5449
Part 1 and BS 6798. The following notes are for
general guidance only .
3.6.1PIPEWORK
It is recommended that copper tubing to BS 2871
Part 1 is used in conjunction with soldered
capillary joints.
Where possible pipes should have a gradient to
ensure air is carried naturally to air release points
and that water flows naturally to drain cocks.
Except where providing useful heat, pipes should
be insulated to avoid heat loss and in particular
to avoid the possibility of freezing. Particular
attention should be paid to pipes passing through
ventilated areas such as under floors, loft space,
and void areas.
3.6.2AUTOMA TIC BY-PASS
The appliance has a built-in automatic by-pass,
consequently there is no requirement for an
external by-pass, however the design of the
system should be such that it prevents boiler
‘cycling’.
The cold feed from the make-up vessel or tank
must be fitted with an approved non-return valve
and stopcock for isolation purposes. The feed pipe
should be connected to the return pipe as close
to the boiler as possible.
3.6.8FREQUENT FILLING
Frequent filling or venting of the system may be
indicative of a leak. Care should be taken during
the installation of the appliance to ensure all
aspects of the system are capable of withstanding
pressures up to at least 3 bar.
Automatic
air-vent
Non-return
valve
Stopcock
Make-up vessel
or tank
5.0 metres minimum
3.6.3DRAIN COCKS
These must be located in accessible positions to
facilitate draining of the appliance and all water
pipes connected to the appliance. The drain cocks
must be manufactured in accordance with BS
2879.
3.6.4AIR RELEASE POINTS
These must be positioned at the highest points
in the system where air is likely to be trapped.
They should be used to expel trapped air and
allow complete filling of the system.
3.6.5EXPANSION VESSEL
The appliance has an integral expansion vessel
to accommodate the increased volume of water
when the system is heated. It can accept up to 8
litres (25/29) or 10 litres (35) of expansion from
within the system, generally this is sufficient,
however if the system has an unusually high
water content, it may be necessary to provide
additional expansion capacity (see 6.19).
3.6.6FILLING POINT
A method for initial filling of the system and
replacing water lost during servicing etc. has been
provided. This method of filling complies with the
current Water Supply (Water Fittings) Regulations
1999 and Water Bylaws 2000 (Scotland).
3.6.7LOW PRESSURE SEALED SYSTEM
An alternative method of filling the system would
be from an independent make-up vessel or tank
mounted in a position at least 1 metre above the
highest point in the system and at least 5 metres
above the boiler (see fig. 5).
Fig. 5
Heating
return
3.7ELECTRICAL SUPPLY
The appliance is supplied for operation on 230V
@ 50Hz electrical supply; it must be protected
with a 3-amp fuse. The method of connection to
the mains electricity supply must allow for
complete isolation from the supply . The preferred
method is by using a double-pole switch with a
contact separation of at least 3mm. The switch
must only supply the appliance and its
corresponding controls, i.e. time clock, room
thermostat, etc. Alternatively an un-switched
shuttered socket with a fused 3-pin plug both
complying with BS 1363 is acceptable.
3.8SHOWERS
If the appliance is intended for use with a shower,
the shower must be thermostatically controlled
and be suitable for use with a combination boiler.
3.9MOUNTING ON A COMBUSTIBLESURFACE
If the appliance is to be fitted on a wall of combustible material, a sheet of fireproof material
must protect the wall.
6
3.10TIMBER FRAMED BUILDINGS
If the appliance is to be fitted in a timber framed
building, it should be fitted in accordance with the
Institute of Gas Engineers publication (IGE/UP/
7) ‘Guide for Gas Installations in Timber Frame
Buildings’.
3.11INHIBITORS
Vokera recommend that a inhibitor – suitable for
use with low water-content, copper heat exchangers – is used to protect the boiler and system
SECTION 3AGENERAL REQUIREMENTS (EIRE)
from the effects of corrosion and/or electrolytic
action. The inhibitor must be administered in strict
accordance with the manufacturers* instructions.
*Fernox and Sentinel manufacture products that
have proved suitable for use with Vokera appliances. Vokera Ltd. cannot comment on the suitability of any other such product with our
appliances.
This appliance must be installed by a competent
person in accordance with and defined by, the
Standard Specification (Domestic Gas
Installations) Declaration (I.S. 813).
3A.1RELATED DOCUMENTS
The installation of this boiler must be in
accordance with the relevant requirements of the
local building regulations, the current ETCI
National Rules for Electrical Installations, and the
bylaws of the local water undertaking.
It should be in accordance also with any relevant
requirements of the local and/or district authority .
3A.2LOCATION OF APPLIANCE
The appliance may be installed in any room or
internal space, although particular attention is
drawn to the requirements of the current ETCI
National Rules for Electrical Installations, and I.S.
813, Annex K.
When an appliance is installed in a room or internal
space containing a bath or shower, the appliance
or any control pertaining to it must not be within
reach of a person using the bath or shower.
The location chosen for the appliance must permit
the provision of a safe and satisfactory flue and
termination. The location must also permit an
adequate air supply for combustion purposes and
an adequate space for servicing and air circulation
around the appliance. Where the installation of the
appliance will be in an unusual location special
procedures may be necessary , refer to I.S. 813 for
detailed guidance on this aspect.
A compartment used to enclose the appliance
must be designed and constructed specifically
for this purpose. An existing compartment/
cupboard may be utilised provided that it is
modified to suit.
This appliance is not suitable for external
installation.
3A.3GAS SUPPLY
The gas meter – as supplied by the gas supplier
– must be checked to ensure that it is of adequate
size to deal with the maximum rated input of all
the appliances that it serves. Installation pipes
must be fitted in accordance with I.S. 813.
Pipe work from the meter to the appliance must
be of adequate size. Pipes of a smaller size than
the appliance gas inlet connection must not be
used. The installation must be tested for
soundness in accordance with I.S. 813.
If the gas supply serves more than one appliance,
it must be ensured that an adequate supply is
maintained to each appliance when they are in
use at the same time.
3A.4FLUE SYSTEM
The terminal should be located where the
dispersal of combustion products is not impeded
and with due regard for the damage and
discoloration that may occur to building products
located nearby . The terminal must not be located
in a place where it is likely to cause a nuisance
(see I.S. 813).
In cold and/or humid weather, water vapour will
condense on leaving the terminal; the effect of
such pluming must be considered.
If installed less than 2m above a pavement or
platform to which people have access (including
balconies or flat roofs) the terminal must be
protected by a guard of durable material. The
guard must be fitted centrally over the terminal.
Refer to I.S. 813, when the terminal is 0.5 metres
(or less) below plastic guttering or 1 metre (or
less) below painted eaves.
3A.5AIR SUPPLY
The following notes are intended for general
guidance only .
This appliance is a room-sealed, fan-flued boiler,
consequently it does not require a permanent air
vent for combustion air supply .
When installed in a cupboard or compartment,
ventilation for cooling purposes is also not
required.
3A.6W ATER CIRCULATION
Specific recommendations are given in I.S. 813.
The following notes are for general guidance only .
7
3A.6.1 PIPEWORK
It is recommended that copper tubing be used in
conjunction with soldered capillary joints.
Where possible pipes should have a gradient to
ensure air is carried naturally to air release points
and that water flows naturally to drain cocks.
Except where providing useful heat, pipes should
be insulated to avoid heat loss and in particular
to avoid the possibility of freezing. Particular
attention should be paid to pipes passing through
ventilated areas such as under floors, loft space,
and void areas.
3A.6.2 AUTOMA TIC BY -P ASS
The appliance has a built-in automatic by-pass,
consequently there is no requirement for an
external by-pass, however the design of the
system should be such that it prevents boiler
‘cycling’.
3A.6.3 DRAIN COCKS
These must be located in accessible positions to
facilitate draining of the appliance and all water
pipes connected to the appliance.
3A.6.4 AIR RELEASE POINTS
These must be positioned at the highest points
in the system where air is likely to be trapped.
They should be used to expel trapped air and
allow complete filling of the system.
3A.6.5 EXP ANSION VESSEL
The appliance has an integral expansion vessel
to accommodate the increased volume of water
when the system is heated. It can accept up to 8
litres (25/29) or 10 litres (35) of expansion from
within the system, generally this is sufficient,
however if the system has an unusually high
water content, it may be necessary to provide
additional expansion capacity (see 6.19).
3A.6.6 FILLING POINT
A method for initial filling of the system and
replacing water lost during servicing etc. has been
provided. Y ou should ensure this method of filling
complies with the local water authority
regulations.
3A.6.7 LOW PRESSURE SEALED SYSTEM
An alternative method of filling the system would
be from an independent make-up vessel or tank
mounted in a position at least 1 metre above the
highest point in the system and at least 5 metres
above the boiler (see fig. 5).
The cold feed from the make-up vessel or tank
must be fitted with an approved non-return valve
and stopcock for isolation purposes. The feed
pipe should be connected to the return pipe as
close to the boiler as possible.
the installation of the appliance to ensure all
aspects of the system are capable of withstanding
pressures up to at least 3 bar.
3A.7ELECTRICAL SUPPLY
The appliance is supplied for operation on 230V
@ 50Hz electrical supply; it must be protected
with a 3-amp fuse. The method of connection to
the mains electricity supply must allow for
complete isolation from the supply . The preferred
method is by using a double-pole switch with a
contact separation of at least 3mm. The switch
must only supply the appliance and its
corresponding controls, i.e. time clock, room
thermostat, etc.
3A.8SHOWERS
If the appliance is intended for use with a shower,
the shower must be thermostatically controlled
and be suitable for use with a combination boiler.
3A.9MOUNTING ON A COMBUSTIBLESURFACE
If the appliance is to be fitted on a wall of
combustible material, a sheet of fireproof material
must protect the wall.
3A.10 TIMBER FRAMED BUILDINGS
If the appliance is to be fitted in a timber framed
building, it should be fitted in accordance with
I.S. 813 and local Building Regulations.
The Institute of Gas Engineers publication (IGE/
UP/7) ‘Guide for Gas Installations in Timber
Frame Buildings’ gives specific advice on this type
of installation.
3A.11 INHIBITORS
Vokera recommend that a inhibitor – suitable for
use with low water-content, copper heat
exchangers – is used to protect the boiler and
system from the effects of corrosion and/or
electrolytic action. The inhibitor must be
administered in strict accordance with the
manufacturers* instructions.
Fernox and Sentinel manufacture products that
have proved suitable for use with Vokera
appliances. Vokera Ltd. cannot comment on the
suitability of any other such product with our
appliances.
3A.12 DECLARATION OF CONFORMITY
A Declaration of Conformity (as defined in I.S.
813) must be provided on completion of the
installation.
A copy of the declaration must be given to the
responsible person and also to the gas supplier
if required.
3A.6.8 FREQUENT FILLING
Frequent filling or venting of the system may be
indicative of a leak. Care should be taken during
8
SECTION 4INSTALLATION
4.1DELIVERY
Due to the weight of the appliance it may be
necessary for two people to lift and attach the
appliance to its mounting. The appliance is
contained within a heavy-duty cardboard carton.
Lay the carton on the floor with the writing the
correct way up.
4.2CONTENTS
Contained within the carton is:
● the boiler
● the fixing jig and wall bracket
● template
● an accessories pack containing appliance
service connections and washers
● the instruction pack containing the installation
& servicing instructions, user instructions,
Benchmark logbook, guarantee registration
card, and a 3-amp fuse
4.3UNPACKING (see fig. 6)
At the top of the carton pull both sides open – do
not use a knife – unfold the rest of the carton
from around the appliance, carefully remove all
protective packaging from the appliance, and lay
the accessories etc. to one side. Protective gloves
should be used to lift the appliance, the appliance
back-frame should be used for lifting points.
Fig. 6A
Fig. 6
4.4PREPARATION FOR MOUNTING THE
APPLIANCE (see fig. 6A)
The appliance should be mounted on a smooth,
vertical, non-combustible surface, which must be
capable of supporting the full weight of the
appliance. Care should be exercised when
determining the position of the appliance with
respect to hidden obstructions such as pipes,
cables, etc.
When the position of the appliance has been
decided, carefully mark the position of the
combined fixing jig and wall- mounting bracket
(see fig. 6A), and – using the template supplied
– mark the position of the flue-hole (if applicable).
4.5FITTING THE FLUE
The top flue outlet permits both horizontal and
vertical flue applications to be considered,
alternatively , the V okera twin flue system can be
utilised if longer flue runs are required.
4.5.1CONCENTRIC HORIZONTAL FLUE
(For concentric vertical flue, see 4.5.2)
(For twin flue applications, see 4.5.3)
The appliance can be used with either the Vokera
condensing 60/100mm concentric flue system or
the optional 80/125mm concentric flue system.
NOTE
These instructions relate only to the Vokera
condensing 60/100mm concentric flue system.
For specific details on the installation of the 80/
125mm concentric flue system please refer to
the instructions supplied.
The appliance flue outlet elbow can be rotated
through 360° on its vertical axis. In addition the
flue may be extended from the outlet elbow in
the horizontal plane (see 2.9). A reduction must
also be made to the maximum length (see table
below) when additional bends are used.
9
Reduction for additional bends
BendReduction in maximum flue length for each bend
Using the template provided, mark and drill a
1 15mm hole for the passage of the flue pipe. The
hole should have a 1° rise from the boiler to
outside, to ensure any condense fluid that forms,
is allowed to drain back to the appliance.
The fixing holes for the wall-mounting bracket/
fixing jig should now be drilled and plugged, an
appropriate type and quantity of fixing should be
used to ensure that the bracket/jig is mounted
securely . Once the bracket/jig has been secured
to the wall, mount the appliance onto the bracket.
Push-fit connection
Terminal or
extension
NOTE
Fit the internal trim to the flue assembly prior to
connecting the flue pipe to the bend.
You must ensure that the entire flue system is
properly supported and connected.
Seal the flue assembly to the wall using cement
or a suitable alternative that will provide
satisfactory weatherproofing.
The exterior trim can now be fitted.
Fig. 7A
“Y” = “X” + 45mm
4.5.1.1 EXTENDING THE FLUE
Connect the bend – supplied with the terminal
kit – to the top of the boiler using clamp (supplied)
see fig. 7. The additional bends & extensions have
push-fit connections, care should be taken to
ensure that the correct seal is made when
assembling the flue system. Connect the required
number of flue extensions or bends (up to the
maximum equivalent flue length) to the flue
terminal (see fig. 7 & 8).
125mm
outer
clamp
Boiler
Fig. 7
FITTING THE HORIZONT AL FLUE KIT
Carefully measure the distance from the centre
of the appliance flue outlet to the edge of the
finished outside wall (dimension X). Add 45mm
to dimension X to give you Dimension Y (see fig
7A). Measure dimension Y from the terminal end
of the concentric flue pipe and cut off the excess
ensuring any burrs are removed. Pass the
concentric flue pipe through the previously drilled
hole. Fit the flue bend to the boiler flue outlet and
insert the concentric flue pipe into the flue bend
ensuring the correct seal is made. Using the
clamp, gasket, and screws supplied, secure the
flue bend to the appliance flue spigot. The 60mm
M & F adaptor (supplied with the flue kit) should
be discarded.
The hole should have a 1° rise from the boiler to
outside, to ensure any condense fluid that forms,
is allowed to drain back to the appliance.
NOTE
When cutting an extension to the required length,
you must ensure that the excess is cut from the
plain end of the extension (see fig. 7 & 8).
Remove any burrs, and check that all seals are
located properly.
You must ensure that the entire flue system is
properly supported and connected.
Seal the flue assembly to the wall using cement
or a suitable alternative that will provide
satisfactory weatherproofing. The interior and
exterior trim can now be fitted.
10
Fig. 8
4.5.2CONCENTRIC VERTICAL FLUE
The appliance can be used with either the Vokera
condensing 60/100mm concentric flue system or
the optional 80/125mm concentric flue system.
NOTE
These instructions relate only to the Vokera
condensing 60/100mm concentric flue system.
For specific details on the installation of the 80/
125mm concentric flue system please refer to
the instructions supplied.
The vertical flue terminal can be connected
directly to the appliance flue outlet. Alternatively,
an extension or bend can be connected to the
appliance flue outlet if desired (see 4.4.2),
however if additional bends are fitted, a reduction
must be made to the maximum flue length (see
table below).
Reduction for bends
BendReduction in maximum flue length for each bend
Using the dimensions given in fig. 9 as a reference, mark
and cut a 115mm hole in the ceiling and/or roof.
Fit the appropriate flashing plate to the roof and insert
the vertical flue terminal through the flashing plate from
the outside, ensuring that the collar on the flue terminal
fits over the flashing.
The fixing holes for the wall-mounting bracket should now
be drilled and plugged, an appropriate type and quantity
of fixing should be used to ensure that the bracket is
mounted securely. Once the bracket has been secured
to the wall, mount the appliance onto the bracket.
Fig. 9
IMPORTANT
The vertical flue terminal is 1.0 metre in length
and cannot be cut; therefore it may be necessary
to adjust the height of the appliance to suit or
use a suitable extension.
Connect the vertical flue assembly to the boiler
flue spigot using the 60mm & 100mm clips,
gaskets, & screws (supplied), ensuring the correct
seal is made. The flue support bracket (supplied
with the vertical flue kit) can now be fitted.
If the vertical flue requires extension/s or
additional bend/s, connect the required number
of flue extensions or bends (up to the maximum
equivalent flue length) between the boiler and
vertical flue assembly (see fig. 8).
Ensure that any horizontal sections of the flue
system have a 1° fall back to the boiler (17mm
per 1000mm).
11
NOTE
When cutting an extension to the required length,
you must ensure that the excess is cut from the
plain end of the extension (see fig. 8). Remove
any burrs, and check that any seals are located
properly.
You must ensure that the entire flue system is
properly supported and connected.
4.5.3TWIN FLUE SYSTEM
The Vokera twin flue system enables greater flue
distances to be achieved (see 4.4.2) than that of
a concentric flue system. It can be used for
horizontal or vertical applications, however the
twin flue system must be converted to the
dedicated concentric flue kit for termination. It is
essential that the installation of the twin flue
system be carried out in strict accordance with
these instructions.
GUIDANCE NOTES ON TWIN FLUE INSTALLATION
● The flue must have a fall back of 1° back to
the appliance to allow any condensate that
may form in the flue system to drain via the
condensate drain. Consideration must also be
given to the fact that there is the possibility of
a small amount of condensate dripping from
the terminal.
● Ensure that the entire flue system is
adequately supported, use at least one bracket
for each extension.
● The entire flue system must be adequately
insulated to maintain heat within the flue
system thereby reducing the possibility of
condensate production.
● As the exhaust outlet pipe can reach very high
temperatures it must be protected to prevent
persons touching the hot surface.
● The condensate drain pipe must be connected
in accordance with building regulations.
MOUNTING THE BOILER
The fixing holes for the wall-mounting bracket should now
be drilled and plugged, an appropriate type and quantity
of fixing should be used to ensure that the bracket is
mounted securely. Once the bracket has been secured
to the wall, mount the appliance onto the bracket.
Pay attention to condense trap!
4.5.3.1 INST ALLATION OF TWIN ADAPTOR KIT (see
fig. 10 & 11)
● Insert the exhaust connection manifold (A)
onto the appliance flue outlet.
● Remove the blanking plate (located to the right
of the appliance flue outlet) and – using the
same screws – install the air inlet plate (B).
● Using the hole in the exhaust connection
manifold as a guide, drill a 3mm hole in the
appliance flue spigot and secure the exhaust
manifold connection to the flue spigot using
the screw provided (C).
● Using the two holes in the air inlet plate as a
guide, drill a 3mm hole in each and secure the
air inlet pipe/bend using the screws provided.
● The twin flue pipes extensions and accessories
can now be installed by pushing together (the
plain end of each extension or bend should
be pushed approximately 50mm into the
female socket of the previous piece).
C
A
B
Reduction for bends
BendReduction in maximum flue length for each bend
● The horizontal terminal is supplied with a built-
in converter box and cannot be shortened.
● A 130mm hole is required for the passage of
the concentric terminal through the wall.
● The air inlet pipe must always be level with or
below, that of the exhaust pipe.
Depending on site conditions it may be preferable
to install the terminal assembly prior to fitting the
twin flue pipes.
Mark and drill a 130mm hole for the passage of
the horizontal flue terminal, ensuring that there
is a 1° fall back to the boiler (17mm per 1000mm).
Insert the terminal assembly into the flue hole.
Push-fit the twin flue pipes onto the concentric to
twin converter box ensuring that the exhaust pipe
connects to the exhaust connection on the
concentric to twin converter.
If necessary cut the plain ends (male) of the twin
flue pipes to allow connection to the concentric
to twin converter
NOTE
Before cutting twin flue pipes ensure allowances
have been made for connection onto the previous
piece and onto the concentric to twin converter.
The last twin Flue pipes must be pushed 50mm
onto the male spigots of the concentric to twin
converter.
NOTE
You must ensure that the entire flue system is
properly supported and connected.
Seal the flue terminal assembly to the wall using
cement or a suitable alternative that will provide
satisfactory weatherproofing. The interior and
exterior trim can now be fitted.
1-deg. = 17mm
1.0-metre
4.5.3.3 VERTICAL TERMINA TION (see fig. 13)
The twin flue system must be converted to the
dedicated concentric flue kit for termination.
● The vertical terminal is supplied with a built-in
converter box and cannot be shortened.
● A 130mm hole is required for the passage of
the concentric terminal through the ceiling and/
or roof.
Depending on site conditions it may be preferable
to install the terminal assembly prior to fitting the
twin flue pipes.
Fit the appropriate flashing plate to the roof and
insert the vertical flue terminal through the
flashing plate from the outside, ensuring that the
collar on the flue terminal fits over the flashing.
Push-fit the twin flue pipes onto the concentric to
twin converter ensuring that the exhaust pipe
connects to the exhaust connection on the
concentric to twin converter.
If necessary cut the plain ends (male) of the twin
flue pipes to allow connection to the concentric
to twin converter.
NOTE
● Before cutting twin flue pipes ensure
allowances have been made for connection
onto the previous piece and onto the
concentric to twin converter. The last twin flue
pipes must be pushed 50mm onto the male
spigots of the concentric to twin converter.
● Y ou must ensure that the entire flue system is
properly supported and connected.
● Ensure that any horizontal sections of pipe
have a 1° fall towards the appliance (17mm
per 1000mm).
13
C/H flow
valve
Fig. 14
C/H return
valve
Safety valve
outlet
4.6.1GAS (see fig. 6A & 14)
The appliance is supplied with a 15mm service
valve, connect a 15mm pipe to the inlet of the
valve and tighten both nuts.
NOTE
It will be necessary to calculate the diameter of
the gas supply pipe to ensure the appliance has
an adequate supply of gas.
Hot water
Outlet
Cold water Inlet
Stopcock/filling
valve
Filling Loop
Gas
Cock
Fig. 13
4.6CONNECTING THE GAS AND W ATER
The appliance is supplied with a fixing jig that
includes service valves (fig. 14). The service
valves are of the compression type. The
accessories pack contains sealing washers etc,
for use with the service valves.
When connecting pipe work to the valves, tighten
the compression end first then insert the sealing
washers before tightening the valve to the
appliance.
NOTE
It will be necessary to hold the valve with one
spanner whilst tightening with another.
4.6.2FLOW & RETURN (see fig. 6A & 14)
The appliance is supplied with 22mm service
valves for the flow and return connections,
connect a 22mm pipe to the inlet of each valve
and tighten both nuts.
NOTE
Depending on system requirements, it may
necessary to increase the size of the flow & return
pipe work after the service valve connections.
4.6.3COLD WATER INLET (see fig. 6A & 14)
The appliance is supplied with a 15mm combined
stopcock and double check-valve, connect a
15mm pipe to the inlet of the stopcock and tighten
both nuts.
4.6.4HOT WATER OUTLET (see fig. 6A & 14)
The appliance is supplied with a 15mm outlet
connection, connect a 15mm pipe to the outlet
connection and tighten both nuts.
4.6.5SAFETY VALVE (see fig. 6A & 14)
Connect the safety valve connection pipe
between the safety valve outlet and the fixing jig.
14
Connect a discharge pipe to the fixing jig
connection and tighten. The discharge pipe must
have a continuous fall away from the appliance
to outside and allow any water to drain away
thereby eliminating the possibility of freezing. The
discharge pipe must terminate in a position where
any water – possibly boiling – discharges safely
without causing damage or injury, but is still
visible.
4.6.6CONDENSE PIPE
During normal operation the boiler produces
condense which is collected in a trap located in
the lower part of the boiler. A flexible pipe
(condense outlet pipe) is connected to the outlet
of the trap. The flexible pipe must be connected
to a plastic waste pipe only. The plastic waste
pipe must have a minimum of a 3° fall towards
the drain. Any external run of pipe should be
insulated to prevent the risk of freezing.
CONNECTING THE CONDENSA TE OUTLET
Gently pull the condense outlet pipe down from
its location inside the boiler until approximately
200mm protrudes from the underside of the boiler.
Connect a suitable plastic (not copper) pipe (no
less than 20mm diameter) to the outlet pipe and
ensure it discharges in accordance with building
regulations or other rules in force.
A
Fig. 15
4.7ELECTRICAL CONNECTIONS
The electrical supply must be as specified in
section 3/3A. A qualified electrician should
connect the electrical supply to the appliance. If
controls – external to the appliance – are
required, a competent person must undertake the
design of any external electrical circuits, please
refer to section 8 for detailed instructions. ANY
EXTERNAL CONTROL OR WIRING MUST BE
SERVED FROM THE SAME ISOLATOR AS
THAT OF THE APPLIANCE. The supply cable
from the isolator to the appliance must be 3-core
flexible sized 0.75mm to BS 6500 or equivalent.
Wiring to the appliance must be rated for
operation in contact with surfaces up to 90°C.
4.7.1CASING REMOVAL
T o gain internal access to the appliance you must
first remove the casing, proceed as outlined
below:
● press the controls cover to release the controls
cover catch
● locate and unscrew the 2 screws that secure
the controls fascia to the appliance casing (see
fig 15)
● gently lower the control fascia until it rests
● remove the 2 screws located at the Left & Right
of the underside of the casing
● lift the casing upward to disengage it from the
top locating hooks and then remove
● store the casing and screws safely until
required. Re-fit in the reverse order.
4.7.2APPLIANCE TERMINAL BLOCK
The appliance terminal block is located on the
left side of the control fascia (see fig. 15). Locate
and remove the screws securing the terminal
block cover.
NOTE
The appliance comes with a factory fitted link to
allow basic operation of the boiler via the mode
selector switch. If it is anticipated that external
controls will be required please refer to the wiring
diagrams in section 8 for more detailed
information.
4.7.3CONNECTING THE MAINS (230V) INPUT (see
fig. 16)
Remove the terminal block cover as described
in 4.7.2. Pass the cable through the cable
anchorage point. At plug M16 on the appliance
control PCB there are 7 terminals from Front to
Back they are:
1. NEUTRAL
2. NEUTRAL (supply for clock)
3. LIVE
4. LIVE (supply to clock)
5. TA
6. TA
7. (Spare)
Connect the supply cable wires (LIVE, and
NEUTRAL) to their corresponding terminals on
the appliance terminal block. Connect the EARTH
wire to the EARTH block (see fig. 16) ensuring
that it’s left slightly longer that the others, this will
prevent strain on the EARTH wire should the
cable become taut.
15
Do not remove the link wire (between T A & Spare)
unless additional external controls are to be fitted
(see section 8).
● remove the clock aperture plate from the
appliance
● remove the push-out blanking disc from the
clock aperture plate (fig. 17)
● secure the clock to the aperture plate using
the screws provided with the clock (fig. 17)
● refit the clock aperture plate ensuring the clock
is positioned the correct way up
● remove the Red link-wire plug from the
appliance clock connector plug
● connect the clock wiring harness to the clock
connector plug
● re-fit the appliance PCB cover and terminal
cover.
The securing screw on the cable anchorage
should now be tightened. This must be done
before the control fascia is re-fitted in the upright
position. The appliance casing and screws can
now be re-fitted.
Fig. 16
4.7.4CONNECTING THE VOKERA TIME CLOCK
(part no. 201 & 202)
The appliance is supplied with a clock connector
plug that is connected to plug M16 on the
appliance terminal block. The clock connector
plug is for use with the clock harness that is
included in the accessory pack and facilitates an
easy connection to the optional Vokera time clock.
Fig. 17
16
To fit the Vokera time clock:
● remove the appliance PCB cover
● remove and discard the wiring harness
supplied with the clock
● using the clock wiring harness supplied in the
accessory pack, connect the 4-wires to the
clock as shown in fig 16.
SECTION 5COMMISSIONING
5.1GAS SUPPLY INSTALLATION
Inspect the entire installation including the gas
meter, test for soundness and purge. Refer to
BS 6891 for specific instruction.
5.2THE HEA TING SYSTEM
The appliance contains components that may
become damaged or rendered inoperable by oils
and/or debris that are residual from the
installation of the system, consequently it is
essential that the system be flushed in
accordance with the following instructions.
Closed
Position
Normal
Operating
Position
Filling
Position
valve full bore to remove any installation debris
from the boiler prior to lighting. Refill the boiler
and heating system as described in 5.3.
5.5FILLING THE HOT WATER SYSTEM
Close all hot water outlets, turn appliance
stopcock to the normal operating position (fig. 18),
slowly open each outlet until air has been expelled
and clear water is discharged. Check pipe-work
etc. for water soundness.
5.6PRE-OPERA TION CHECKS
Before attempting the initial lighting of the
appliance, the following checks must be
carried out:
● ensure all gas service valves from the meter
to the appliance are open and the supply pipe
has been properly purged
● ensure the proper electrical checks have been
carried out, (see 7.7) particularly continuity,
polarity, and resistance to earth
● ensure the 3 amp fuse – supplied with the
appliance – has been fitted.
● ensure the system has been filled, vented, and
the pressure set to 1 bar.
● ensure the flue system has been fitted properly
and in accordance with the instructions.
● ensure all appliance service valves are open.
Fig. 18
5.3INITIAL FILLING OF THE SYSTEM
Ensure both flow and return service valves are
open, remove appliance casing as described in
4.7.1, identify the automatic air release valve and
loosen the dust cap by turning the cap anticlockwise one full turn. IMPORTANT, THERE
ARE NO MANUAL AIR RELEASE VALVES
LOCATED ON THE APPLIANCE. Ensure all
manual air release valves located on the heating
system are closed. Connect the filling loop as
shown in fig. 6, slowly proceed to fill the system
by firstly opening the inlet valve connected to the
flow valve, and then turning the lever on the
combined stopcock and check valve, to the filling
position (see fig. 18). As water enters the system
the pressure gauge will begin to rise. Once the
gauge has reached 1 bar close both valves and
begin venting all manual air release valves,
starting at the lowest first. It may be necessary
to go back and top-up the pressure until the entire
system has been filled. Inspect the system for
water soundness, rectifying any leaks.
5.4INITIAL FLUSHING
The whole of the heating system must be flushed
both cold and hot as detailed in 5.8. Open all
radiator or heating valves and the appliance flow
& return service valves. Drain the boiler and
system from the lowest points. Open the drain
5.7INITIAL LIGHTING
Ensure the electrical supply to the appliance is
switched on. Move the selector switch to the
Heating & Hot Water position, ensure the time
clock is switched to an ‘ON’ position and ensure
any other external controls are also calling for
heat.
The appliance will now operate in the pre-heat
mode as described in 1.2. Once the pre-heat
function has been completed, the appliance will
operate in the central heating mode as described
in 1.3. Should the appliance fail to ignite, refer to
5.6 and/or section 7 (faultfinding).
5.7.1CHECKING THE BURNER PRESSURE
Although the burner pressure is factory set, it is
necessary to check it during commissioning.
Isolate the appliance from the electrical supply
and attach a suitable manometer to the gas valve
outlet test-point (see fig. 19). Light the boiler as
described in 5.7, turn the Hot Water temperature
selector to maximum, and open fully a DHW outlet
(preferably the bath), allowing the appliance to
stabilise. Compare the reading on the manometer
with the value described in 2.3. If adjustment is
required, follow the detailed instructions in section
7 (7.3).
Once the burner pressure has been checked,
close the DHW outlet, isolate the appliance from
the electrical supply , remove the manometer, and
tighten the gas valve outlet test nipple.
17
Outlet
test-point
Protective
cap
Inlet
test-point
Fig. 19
5.8FINAL FLUSHING OF THE HEA TING SYSTEM
The system shall be flushed in accordance with
BS 7593. If a cleanser is to be used, it shall be
from a reputable manufacturer* and shall be
administered in strict accordance with the
manufacturers instructions.
*Both Sentinel and Fernox manufacture products
that have proved suitable for use with Vokera
appliances. Vokera Ltd. cannot comment on the
suitability of any other such product with our
appliances.
5.8.1INHIBITORS
See Section 3 “general requirements”.
5.11REGULATING THE HOT W A TER
The appliance is fitted with a flow rate restrictor
that limits the maximum flow rate that can be
drawn through the appliance.
Syntesi 25
8-litre9-litre
(Orange)(Blue)
FittedSpare
Syntesi 29
9-litre10-litre11-litre
(Orange)(Blue)(Beige)
SpareFittedSpare
Syntesi 35
11-litre12-litre13-litre
(Beige)(Red)(Olive)
SpareFittedSpare
The restrictor eliminates the need to manually
adjust the DHW flow rate. However if it is felt
necessary to further increase or decrease the
available flow rate, spare restrictors are included
in the accessory pack.
The spare flow rate restrictors can be fitted to
either increase or decrease the maximum flow
rate. The tables above denote the size of restrictor
fitted and the spare restrictors supplied in the
accessory pack. Each restrictor is colour-coded
to enable identification.
5.9SETTING THE BOILER OPERATING TEMPERA TURE
The flow outlet temperature can be adjusted
between 40°C - 80°C via the Heating thermostat
knob (see fig.1).
5.9.1SETTING THE DOMESTIC HOT WATER TEMPERA TURE
The DHW outlet temperature can be adjusted
between 40°C - 65°C via the Hot Water
thermostat knob (see fig.1).
5.10SETTING THE SYSTEM DESIGN PRESSURE
The design pressure should be a minimum of 1
bar and a maximum of 1.5 bar.
The actual reading should ideally be 1 bar plus
the equivalent height in metres (0.1 bar = 1 metre)
to the highest point in the system above the base
of the appliance (up to the maximum of 1.5 bar
total).
N.B. The safety valve is set to lift at 3 bar/30
metres/45 psig.
To lower the system pressure to the required
value, pull lever on head of safety valve to release
water until the required figure registers on the
pressure gauge (see fig. 1).
5.11.1 CHANGING THE FLOW RESTRICTOR
Refer to 6.19 for detailed instruction on changing
the flow restrictor.
5.11.2 REGULATING THE CENTRAL HEATING
SYSTEM
Fully open all radiator and circuit valves and run
the appliance for both heating and hot water until
heated water is circulating. If conditions are warm
remove any thermostatic heads. Adjust radiator
return valves and any branch circuit return valves
until the individual return temperatures are correct
and are approximately equal.
5.12FINAL CHECKS
● ENSURE ALL TEST NIPPLES ON THE
APPLIANCE GAS VALVE HAVE BEN
TIGHTENED AND CHECKED FOR
SOUNDNESS.
● ENSURE THE APPLIANCE FLUE SYSTEM
IS FITTED CORRECTL Y AND IS PROPERL Y
SECURED.
● ENSURE ALL PIPE WORK IS RE-CHECKED
FOR SOUNDNESS.
● RE-FIT APPLIANCE CASING.
● COMPLETE APPLIANCE LOGBOOK.
18
Complete details of the boiler, controls,
installation, and commissioning in the logbook
supplied with the boiler. This is an important
document, which must be correctly completed
and handed to the user. Failure to install and
commission the appliance to the manufacturers
instructions may invalidate the warranty .
5.13INSTRUCTING THE USER
Hand over all documentation supplied with this
appliance – including these instructions – and
explain the importance of keeping them in a safe
place.
Explain to the user how to isolate the appliance
from the gas, water, and electricity supplies, and
the locations of all drain points.
SECTION 6SERVICING
Show the user how to operate the appliance and
any associated controls correctly.
Show the user the location of the filling valve and
how to top-up the system pressure correctly , and
show the location of all manual air release points.
Explain to the user how to turn off the appliance
for both long and short periods and advise on
the necessary precautions to prevent frost
damage.
Explain to the user that for continued safe and
efficient operation, the appliance must be
serviced annually by a competent person.
6.1GENERAL
To ensure the continued safe and efficient
operation of the appliance, it is recommended
that it is checked and serviced at regular intervals.
To ensure correct and safe operation of the
appliance, it is essential that any worn or failed
component be replaced only with a genuine
Vokera spare part.
The frequency of servicing will depend upon the
particular installation conditions, but in general,
once per year should be adequate.
It is the law that any servicing work is carried out
by competent person such as a Vokera engineer ,
an approved service agent, British Gas, or other
CORGI registered personnel.
The following instructions apply to the appliance
and its controls, but it should be remembered that
the central heating and the domestic hot water
systems would also require attention from time
to time.
6.2ROUTINE ANNUAL SERVICING
Check the operation of the appliance and ensure
it functions as described in section 7. Compare
the performance of the appliance with its design
specification. The cause of any noticeable
deterioration should be identified and rectified
without delay .
Thoroughly inspect the appliance for signs of
damage or deterioration especially the flue
system and the electrical apparatus.
Check and adjust – if necessary – all burner
pressure settings (see 7.3).
Check and adjust – if necessary – the system
design pressure (see 5.10).
Carry out an analysis of the flue gases (see 7.4),
and visually check the condition of the entire flue
assembly .
Compare the results with the appliance design
specification.
Any deterioration in performance must be
identified and rectified without delay .
Ensure both flue venturis are clean and free from
any debris or obstruction.
Ensure the burner, main heat exchanger, and
latent heat collector are clean and free from any
debris or obstruction.
6.3REPLACEMENT OF COMPONENTS
Although it is anticipated that this appliance will
give years of reliable, trouble free service, the
life span of components will be determined by
factors such as operating conditions and usage.
Should the appliance develop a fault, the fault
finding section will assist in determining which
component is malfunctioning.
6.4COMPONENT REMOV AL PROCEDURE
TTo remove a component, access to the interior
of the appliance is essential. Isolate the appliance
from the electrical supply and remove the fuse.
And when necessary , close all service valves on
the appliance, remove the appliance casing as
described in section 4.7.1, and drain the water
content from the appliance via the safety valve.
Ensure some water absorbent cloths are
available to catch any residual water that may
drip from the appliance or removed component.
Undertake a complete commissioning check as
detailed in section 5, after replacing any
component. ALWAYS TEST FOR GAS
SOUNDNESS IF ANY GAS CARRYING
COMPONENTS HAVE BEEN REMOVED OR
DISTURBED.
6.5PUMP ASSEMBLY (see fig. 20)
Carry out component removal procedure as
described in 6.4.
Disconnect and remove the ancillary items
(3,4,5,6,7) from the pump assembly . Slacken and
remove the securing screw (8) from the heating
manifold. Disconnect the electrical cover & lead
(1,2). The pump assembly can now be removed
from the heating manifold. Replace in the reverse
order.
19
Fig. 20
6.6SAFETY V ALVE (see fig. 21)
Carry out component removal procedure as
described in 6.4.
Disconnect the outlet pipe from the safety valve,
remove safety valve locking screw (1) from the
heating manifold. Replace in the reverse order.
Fig. 22
6.9PRESSURE GAUGE (see fig. 23)
Carry out component removal procedure as
described in 6.4.
Remove pressure gauge locking screw (1),
located on pump base, and withdraw the pressure
gauge pipe (2), locate the spring tabs on the
pressure gauge body, push and hold tabs in, to
enable extraction of the gauge from its location.
Replace in the reverse order.
Fig. 21
6.7AUTOMATIC AIR RELEASE VALVE (see fig.
20) (AAV)
Carry out component removal procedure as
described in 6.4.
Using a suitable pair of pump pliers, unscrew the
AA V from the rear of the pump assembly. Replace
in the reverse order.
6.8WATER PRESSURE SWITCH (see fig. 22)
Carry out component removal procedure as
described in 6.4.
Remove locking screw (1) and the water pressure
switch from the heating manifold, and – after
taking note of the electrical connections –
disconnect the wiring. Replace in the reverse
order.
20
Fig. 23
6.10PRIMARY THERMISTOR (see fig. 24)
Carry out component removal procedure as
described in 6.4.
Unclip and remove the air chamber cover, and
remove the right side air baffle.
Disconnect thermistor electrical plug. Using a
13mm spanner slacken and remove the
thermistor and sealing washer (1, 2) from the
main heat exchanger. Replace in the reverse
order.
Fig. 24
Fig. 26
6.11HIGH LIMIT THERMOSTAT (see fig. 25)
Carry out component removal procedure as
described in 6.4.
Unclip and remove the air chamber cover.
Pull off electrical connections from the high limit
thermostat (2), slacken and remove retaining
screws (3). Replace in reverse order.
NOTE
Ensure that any replacement PCB has the correct
‘Jumper Tag’ configuration (see section 8).
6.13GAS VALVE (see fig. 27)
Carry out component removal procedure as
described in 6.4.
The gas valve must be changed as complete unit.
Disconnect the electrical plug and leads from the
gas valve. Slacken and unscrew gas valve inlet
and outlet connections (3). Please note, the
sealing washers (2) must be discarded and
replaced with new sealing washers (2). Locate
and remove gas valve retaining screws on the
underside of the boiler if required, the gas valve
can now be removed. Replace in the reverse
order. Check and adjust burner pressure settings.
WARNING, A GAS SOUNDNESS CHECK
MUST BE CARRIED OUT.
Fig. 25
6.12PRINTED CIRCUIT BOARD (see fig. 26)
Carry out component removal procedure as
described in 6.4.
Locate and remove the screws (1) which secure
the PCB cover & terminal cover, then remove
cover, after carefully taking note of all wiring
connections, disconnect all wiring from the PCB,
locate and remove the PCB securing screws
(2,3,), remove the required PCB (4,5,6). Replace
in the reverse order.
Fig. 27
21
6.14INTEGRAL TIME SWITCH (if fitted)
Carry out component removal procedure as
described in 6.4.
Locate and remove the terminal cover and
securing screws (2), locate and remove the time
clock retaining screws, remove time clock.
Disconnect wiring after carefully taking note of
all electrical connections. Replace in the reverse
order.
6.15ELECTRODE, BURNER THERMOSTAT,
BURNER & INJECTORS (see fig. 28)
Carry out component removal procedure as
described in 6.4.
Unclip and remove the air chamber cover (2).
Locate and remove the 6 screws securing the
front combustion cover (3), pull the cover towards
you before lifting and disengaging. Disconnect
the electrode lead and burner thermostat from
their respective connectors. Ease the electrode
sealing grommet from its seating (4). Remove the
retaining screw (6) for the burner thermostat and
remove the thermostat (7).
Fig. 29
Locate and remove the four screws which secure
the burner in position (1), gently ease the burner
out of its location. Once the burner has been
removed, the electrode retaining screw can be
can be removed. Locate the burner injectors (2)
and remove (if necessary). Replace in the reverse
order. Please note, the injector sealing washers
(3) must be replaced if the injectors have been
removed, ensure all seals are in good condition,
taking care to ensure they are replaced correctly .
Replace in the reverse order.
1
1
Fig. 29
3
2
1
1
5
1
4
3
2
Fig. 28
22
6.16FLUE FAN (see fig. 28 & 30)
Carry out component removal procedure as
described in 6.4.
Fig. 28: unclip and remove the air chamber cover,
gently pull the cover towards you before lifting
and disengaging (2). Locate and remove the six
screws that secure the front combustion cover,
then remove the cover (3).
Fig. 30: disconnect the electrical connections and
silicone tubes (10) attached to the fan, noting their
positions. Locate and remove the screws (6) that
secure the analogue pressure switch assembly
(4&5). Locate and remove the screws that secure
the flue hood and air baffle, disconnect the flue
clip (1) from the fan-flue elbow, and gently ease
the fan (3) & flue hood assembly (2) from its
location. Locate and remove the four screws that
secure the fan to the flue hood. Remove the fan
to flue elbow. Replace in the reverse order . Ensure
all seals are in good condition, taking care to
ensure they are replaced correctly .
6
6
4
4
5
5
8
8
9
9
3
3
7
7
1
1
10
10
Fig. 30
6.17MAIN HEAT EXCHANGER (see fig. 28 & 31)
Carry out component removal procedure as
described in 6.4.
Fig. 28: unclip and remove the air chamber cover,
gently pull the cover towards you before lifting
and disengaging (2). Locate and remove the six
screws that secure the front combustion cover,
then remove the cover (3).
Fig. 31: remove the air chamber side panels if
3
2
2
necessary by unscrewing the securing screws
(3). Disconnect the flow and return connections
(4, 5) on the heat exchanger. The heat exchanger
can now be withdrawn from the appliance.
Replace in the reverse order. Ensure all seals
are in good condition, taking care to ensure they
are replaced correctly.
4
4
3
Fig. 31
5
5
2
1
2
23
6.18AIR PRESSURE SWITCH (see fig. 30)
Carry out component removal procedure as
described in 6.4.
Fig. 28: unclip and remove the air chamber cover,
gently pull the cover towards you before lifting
and disengaging (2).
Fig. 30: locate and remove the two screws (6)
holding the air pressure switch to the air chamber.
Disconnect the electrical connections and silicone
tubes (10) attached to the air pressure switch,
noting their positions. Replace in the reverse
order. Ensure all seals are in good condition,
taking care to ensure they are replaced correctly .
6.19FLOW RESTRICTOR (see fig. 32)
Carry out the component removal procedure as
described in 6.4.
Slacken the cold water inlet pipe (1) at the DHW
flow switch. Disconnect the cold-water inlet pipe
(2) from the DHW heat exchanger and move it to
the side. Using a small screwdriver, gently ease
the flow restrictor (6) from its seating. Replace in
the reverse order. Ensure all seals are in good
condition, taking care to ensure they are replaced
correctly .
inserted into the DHW manifolds. Ensure all seals
are in good condition, taking care to ensure they
are replaced correctly.
If necessary remove the condense trap as
described in 6.29.
Fig. 33
6.22VALVE ACTUA TOR (see fig. 34)
Carry out component removal procedure as
described in 6.4.
Remove the locking pin (1) that secures the
actuator to the heating manifold. Disconnect the
electrical plug (2) from the actuator. Replace in
the reverse order.
6.20DHW FLOW SWITCH (see fig. 32)
Carry out component removal procedure as described in 6.4.
Disconnect and remove the cold water inlet pipe
(1, 2) from the DHW flow switch & DHW heat
exchanger. Disconnect the wiring to the DHW flow
switch. Remove the locking pin (3) from the DHW
flow switch and lift the DHW flow switch housing
from its seating, taking care not to lose the float
contained within the housing. Replace in the
reverse order ensuring that the housing is firmly
inserted onto its seating. Ensure all seals are in
good condition, taking care to ensure they are
replaced correctly .
Fig. 34
6.23DIVERTOR VALVE ASSEMBLY (see fig. 35)
Carry out component removal procedure as
described in 6.4.
Remove the valve actuator as described in 6.22.
Locate and remove the 5-screws (2) that secure
the valve housing cover to the heating manifold.
Gently prise the valve seating assembly and
cover (3) from the manifold. Replace in the
reverse order ensuring that the seating assembly
is inserted properly . Ensure all seals are in good
condition, taking care to ensure they are replaced
correctly.
Fig. 32
6.21DHW HEAT EXCHANGER
Carry out component removal procedure as
described in 6.4.
Locate and remove the screws (1) that secure
the heat exchanger to the DHW manifolds.
Carefully remove the heat exchanger from its
location taking care not to spill any residual water.
Replace in the reverse order ensuring that the
heat exchanger ‘O’ ring seals are correctly
24
Fig. 35
6.24SECONDARY THERMISTOR (see fig. 36)
Carry out component removal procedure as
described i 6.4. Pull back the protective cover
from the thermistor and disconnect the electrical
plug. Using a 13mm spanner slacken and remove
the thermistor and sealing washer from the DHW
heat exchanger manifold. Replace in the reverse
order.
Fig. 36
6.25AUTOMATIC BYPASS (see fig. 37)
Carry out component removal procedure as
described in 6.4.
Disconnect and remove the flow pipe at the
heating manifold & DHW manifold (1), and at the
connection to the air chamber. Using a hooked
piece of wire, carefully withdraw the bypass
cartridge (2). Ensure all seals are in good
condition, taking care to ensure they are replaced
correctly. Replace in the reverse order ensuring
the cartridge is facing the correct way .
Fig. 37
6.26DHW NON-RETURN VALVE (see fig. 38)
Carry out component removal procedure as
described in 6.4.
Disconnect and remove the flow pipe at the
heating and DHW manifold (1), and at the
connection to the air chamber. Using a hooked
piece of wire, carefully withdraw the non-return
cartridge (2). Ensure all seals are in good
condition, taking care to ensure they are replaced
correctly. Replace in the reverse order ensuring
the cartridge is facing the correct way .
Fig. 38
6.27EXPANSION VESSEL fig. 1
Should the removal and replacement of the
expansion vessel be deemed impractical, an
external expansion vessel may be fitted to the
return pipe as close to the appliance as possible.
Carry out component removal procedure as
described in 6.4.
Disconnect the flue from the appliance.
Disconnect the flexible expansion pipe from the
vessel (fig. 39). Locate and remove the four
screws that secure the vessel top holding plate,
remove the plate. The expansion vessel can now
be removed. Replace in the reverse order. Ensure
all seals are in good condition, taking care to
ensure they are replaced correctly .
Carry out component removal procedure as
described in 6.4.
Disconnect the flue elbow or pipe from the
appliance flue outlet. Unclip and remove the air
chamber cover, gently pull the cover towards you
before lifting and disengaging. Remove the RH
side panel of the air chamber. Disconnect the
wiring to the fan, pressure switch, primary
thermistor, & overheat thermostat. Carefully
unclip the wires from the air chamber and
withdraw the wiring & grommet from the air
chamber. Disconnect the electrode lead and
burner thermostat wires. Disconnect the outlet
gas pipe, the flow & return pipes, and the
condense pipe from the air chamber.
Locate and remove the 2-screws that secure the
lower section of the air chamber. Locate and
remove the 2-screws that secure the upper
section of the air chamber. The complete air
chamber assembly can now be lifted clear from
the appliance. Disconnect the flexible expansion
pipe from the vessel (fig. 39). Locate and remove
the 2-screws that secure the vessel (1). The
expansion vessel can now be removed. Replace
in the reverse order. Take extreme care when
refitting the wiring to the air chamber. Ensure all
seals are in good condition, taking care to ensure
they are replaced correctly .
25
6.28LATENT HEAT COLLECTOR fig’s. 40 & 41
Carry out component removal procedure as
described in 6.4. Remove the flue hood and fan
assembly as detailed in 6.16. Disconnect the
condense sensor wire from the sensor.
Fig. 40: disconnect and remove the inlet (1),
outlet (3) and condense pipes (2) from the
collector.
Fig. 41: unscrew and remove the 3 screws (1)
that secure the collector to the air chamber and
disconnect the collector (2) from the flue
connection. Replace in the reverse order ensuring
all seals are intact and located correctly.
6
6
4
4
6
6
5
5
2
2
1
1
Fig. 39
1
4
4
Fig. 40
3
3
6.28A DISMANTLING THE LATENT HEAT
COLLECTOR (see fig. 42)
During routine servicing or maintenance, there
is no requirement to remove or dismantle the
collector, however should it be deemed
necessary to dismantle the collector, all seals
should be discarded and replaced with new ones.
6.29CONDENSE TRAP REMOVAL (see fig. 43)
Carry out component removal procedure as
described in 6.4. Disconnect the flexible (outlet)
condense pipe from the condense trap (1).
Disconnect the rigid (inlet) condense pipe from
the condense trap (2). Locate and remove the
pins that secure the trap to the lower frame of
the boiler (3). Carefully remove the condense trap.
Replace in the reverse order.
If necessary remove the upper connection of the
pipe (4).
9
9
6
6
2
Fig. 41
2
4
1
Fig. 42
26
8
8
4
4
7
7
5
5
3
3
2
2
1
1
Fig. 43
3
3
SECTION 7CHECKS, ADJUSTMENTS AND FAULT FINDING
7.1CHECKING APPLIANCE OPERATION
When carrying out any repairs or servicing to the
appliance, the relevant commissioning procedure
must be undertaken to ensure the continued safe
operation of the appliance. Particular attention
should be made to ensure gas soundness, water
soundness and the electrical integrity of the
appliance.
7.2APPLIANCE MODE OF OPERATION
NOTE: there must be sufficient system water
pressure (min. 0.5 bar) to ensure the water
pressure switch is activated. If there is insufficient
system pressure the pump and fan will be
prevented from operating.
7.2.1SELECTOR SWITCH IN THE OFF POSITION
When the selector switch is in the OFF position,
there is no LED display or LED status indicator.
The divertor valve is in the DHW position. The
appliance will not respond to any DHW or heating
requests.
Active Functions:
● frost-protection system
● pump anti-block
● valve actuator anti-block.
7.2.2SELECTOR SWITCH IN THE HOT WATER
ONLY POSITION
When the selector switch is in the HW only
position, the status LED is illuminated and the
LED display shows the current temperature
measured at the secondary (DHW) thermistor.
The divertor valve is in the DHW position. The
appliance will respond to any DHW requests.
Active Functions:
● DHW pre-heat
● frost-protection system
● pump anti-block
● valve actuator anti-block.
7.2.3SELECTOR SWITCH IN THE HEATING & HOT
WATER POSITION
When the selector switch is in the Heating & HW
position, the status LED is illuminated and the
LED display shows the current temperature
measured at the secondary (DHW) thermistor.
The divertor valve is in the DHW position. The
appliance will respond to any Heating or DHW
requests.
Active Functions:
● DHW pre-heat
● frost-protection system
● pump anti-block
● fan anti-block
● valve actuator anti-block.
7.2.4 APPLIANCE FUNCTIONS
● DHW pre-heat: this function is only active
when there are no requests for heating or hot
water. When the secondary thermistor drops
to 35°C, the pre-heat function is enabled, the
appliance operates on minimum power until
the secondary thermistor reaches 55°C.
Thereafter the pump and fan will over-run for
10-seconds.
● Frost-protection: this function is only active
when there are no requests for heating or HW.
Should the temperature of the primary
thermistor drop below 7°C, the valve actuator
will motor to the heating position, and the pump
will be activated for approximately 20-minutes.
Should the temperature of the primary
thermistor excee 10°C during this period, the
cycle will be aborted. If the temperature drops
below 4°C, the boiler will operate on minimum
power until the temperature of the primary
thermistor reaches 30°C. Thereafter the pump
& fan will over-run for 30-seconds.
● Anti-block cycle: when there has been no
heating or HW request for 19-hours, the antiblock cycle is activated. The valve actuator will
motor from the DHW position to the heating
position for a period of 10-seconds and then
motor back to the DHW position. Thereafter
the pump will be activated for a period of 1minute. If the selector switch is in the Heating
& HW position, the fan will also be active for 1minute.
7.2.5HEATING MODE
With the selector switch in the Heating & HW
position and any additional controls (time clock,
room thermostat, etc.) calling for heat, the
appliance will operate in the heating mode. The
valve actuator will motor to the heating position
and the pump and fan will be active. The operation
of the fan causes the analogue pressure switch
(PAD) to deliver a signal voltage to the control
PCB. If the signal voltage is sufficient a slow
ignition sequence is enabled, whereby the current
supplied to the gas valve modulating coil is
progressively increased from minimum to
maximum over a period of 8-seconds. During this
period the ignition electrode sparks continuously
even if the burner has ignited.
NOTE
If the spark/sensing electrode does not sense
ignition the appliance will then go to lockout.
Ignition is sensed by the electronic circuitry to
ensure flame stability at the burner. Once
successful ignition has been achieved, the
electronic circuitry allows 75% of the full gas rate
through the appliance. After 15 minutes the gas
rate is increased to maximum (100%).
When the set-point has been reached (the
position of the heating temperature selector) as
measured at the primary thermistor, the appliance
will begin the modulation phase whereby the fan
and gas valve will continuously modulate to
maintain the set-point. If the temperature
continues to rise and exceeds the set-point by
6°C, the burner will shut down and the boiler will
perform a three-minute anti-cycle (timer delay).
A new ignition sequence will be enabled when
the 3-minute anti-cycle has been performed and
27
the temperature at the primary thermistor has
dropped 6°C below the set-point.
NOTES
The timer delay can be de-activated by the
insertion of a ‘jumper’ on the PCB or by isolating
the appliance from the electrical supply for 30
seconds.
Any DHW request will always have priority over
the heating request.
When the request for heating has been satisfied,
the appliance pump and fan may continue to
circulate to dissipate any residual heat within the
appliance.
7.2.6DHW MODE
With the selector switch in the Heating & HW
position, or HW only position, and a DHW outlet
is opened, the appliance will operate in the HW
mode. The valve actuator will motor to the HW
position (if a heating request was active) and the
pump and fan will be active. The operation of the
fan causes the analogue pressure switch (P AD)
to deliver a signal voltage to the control PCB. If
the signal voltage is sufficient a slow ignition
sequence is enabled, whereby the current
supplied to the gas valve modulating coil is
progressively increased from minimum to
maximum over a period of 8-seconds. During this
period the ignition electrode sparks continuously
even if the burner has ignited.
NOTE
If the spark/sensing electrode does not sense
ignition the appliance will then go to lockout.
Ignition is sensed by the electronic circuitry to
ensure flame stability at the burner. Once
successful ignition has been achieved, the
electronic circuitry modulates the appliance
output in order to achieve the DHW set-point (the
position of the DHW temperature selector) as
measured at the secondary thermistor.
When the set-point has been reached, the
appliance will begin the modulation phase
whereby the fan and gas valve will continuously
modulate to maintain the set-point.
If the temperature continues to rise and exceeds
the set-point by 5°C, the burner will shut down
until the temperature drops to set-point + 4°C,
whereby a new ignition sequence will be enabled.
When the request for heating has been satisfied,
the appliance fan may continue to operate to
dissipate any residual heat from within the
appliance.
described in 2.3. If adjustment is required, remove
the protective cap from the gas valve modulating
coil assembly and turn the outer (10mm) nut
clockwise to increase, or counter-clockwise to
decrease the burner pressure.
Fig. 44
NOTE
Always check and/or adjust the minimum and
maximum gas pressures whilst the appliance is
in the HW only mode. Ensure a DHW outlet
(preferably the bath) is fully open, and that the
HW temperature selector is at maximum.
7.3.2SETTING THE MIMIMUM BURNER PRESSURE
(see fig. 45)
Once the maximum burner pressure has been
checked and/or adjusted, remove one of the grey
wires from the modulating coil. Compare the
reading on the manometer with the value
described in 2.3. If adjustment is required, turn
the inner (red) crosshead screw clockwise to
increase, or counter-clockwise to decrease the
burner pressure, whilst ensuring that the outer
(10mm) nut does not move. When checking and/
or adjustment has been completed, isolate the
appliance from the electrical supply, replace the
protective cap, refit the grey wire to the
modulating coil, remove the manometer and
tighten the outlet test nipple.
IMPORTANT, A GAS SOUNDNESS CHECK
MUST BE CARRIED OUT.
7.3CHECKING AND ADJUSTING BURNER PRESSURE (see fig. 19)
Although the burner pressure is factory set, it is
necessary to check it during servicing or if the
gas valve has been removed.
Isolate the appliance from the electrical supply
and attach a suitable manometer to the gas valve
outlet test nipple.
7.3.1SETTING THE MAXIMUM BURNER PRESSURE (see fig. 44)
Light the boiler as described in 5.7 and compare
the reading on the manometer with the value
28
Fig. 45
7.4COMBUSTION ANAL YSIS TEST
A combustion analysis check can easily be
carried out on the appliance via the test points
located on the top of the appliance, however you
must check that the burner pressures are set
correctly (see 7.3).
● Insert the flue gas analyser probe into the right
hand test point (see fig 46).
● Locate and remove the protective cap that
conceals the ‘CO mode’ butto (see fig. 46).
● Light the boiler as described in 5.7 and press
the ‘CO mode’ button once.
● The boiler will now enter the combustion
analysis mode (CO mode) for a period of 15
minutes. During this time it will remain on full
gas and ‘CO’ will be displayed on the LED
display.
● Once the flue gas analysis has been made,
press the ‘CO mode’ to resume normal
operation.
Fault codePossible causes
01Gas supply problem
Gas line requires purging
Reversed polarity
Broken, internal flue joint
02Flow/return valves closed
Stuck pump
03Debris in flue system
Debris in flue venturi
04Insufficient water pressure
Air in boiler
Protecting
cap
Air analysis outletFumes analysis outlet
Fig. 46
7.5CHECKING THE EXP ANSION VESSEL
Carry out the component removal procedure as
described in 6.4. Y ou must ensure that the boiler
is completely drained of water.
Using a suitable pressure gauge, remove dust
cap on expansion vessel and check the charge
pressure. The correct charge pressure should be
1.0 bar ± 0.1 bar.
If the charge pressure is less, use a suitable pump
to increase the charge.
NOTE
You must ensure the safety valve is in the open
position whilst re-charging takes place. Replace
the dust cap and carry out the relevant
commissioning procedure (section 5).
7.6EXTERNAL F AUL TS
Before carrying out any faultfinding or component
replacement, ensure the fault is not attributable
to any aspect of the installation.
7.6.1 INST ALLA TION F AUL TS
SymptomPossible causes
No ignitionCheck wiring
Check electrical supply
No hot waterCheck hot/cold pipe
work is not reversed
No central heatingCheck wiring of time clock
and/or room thermostat
7.7ELECTRICAL CHECKS
Any electrical checks must be carried out by a
suitably qualified person.
7.7.1EARTH CONTINUITY TEST
Isolate the appliance from the electrical supply,
and using a suitable multi-meter carry out a
resistance test. Connect test leads between an
appliance earth point and the earth wire of the
appliance supply cable. The resistance should
be less than 1 OHM. If the resistance is greater
than 1 OHM check all earth wires and connectors
for continuity and integrity .
7.7.2SHORT CIRCUIT CHECK
Isolate the appliance from the electrical supply , and
using a suitable multi-meter, carry out a short circuit
test between the Live & Neutral connections at the
appliance terminal strip (fig.16).
Repeat above test on the Live & Earth connections
at the appliance terminal strip (fig.16).
NOTE
Should it be found that the fuse has failed but no
fault is indicated, a detailed continuity .
Check will be required to trace the fault. A visual
inspection of components may also assist in
locating the fault.
7.7.3POLARITY CHECK
With the appliance connected to the electrical
supply and using a suitable multimeter, carry out
the following voltage tests:
● connect test leads between the Live & Neutral
connections at the appliance terminal strip
(fig.16). The meter should read approximately
230V ac. If so proceed to next stage. If not,
see 7.7.4.
● connect test leads between the Live & Earth
connections at the appliance terminal strip
(fig.16). The meter should read approximately
230V ac. Iff so proceed to next stage. If not,
see 7.7.4.
● connect test leads between the Neutral & Earth
connections at the appliance terminal strip
(fig.16). The meter should read approximately
0 – 15Vac. If so polarity is correct. If not, see
7.7.4.
7.7.4REVERSED POLARITY OR SUPPL Y FAULT
Repeat the above tests at the appliance isolator,
if testing reveals correct polarity and/or supply at
the isolator, re-check wiring and connections
between the isolator and the appliance.
If tests on the isolator also reveal reversed polarity
29
or a supply fault, consult the local electricity
supplier for advice.
7.7.5RESISTANCE T O EARTH CHECK
Isolate the appliance from the electrical supply,
and using a suitable multi-meter carry out a
resistance test. Connect test leads between the
Live & Earth connections at the appliance
terminal strip (fig.16). If the meter reads other
than infinity there is a fault that must be isolated,
carry out a detailed continuity check to identify
the location of the fault.
IMPORTANT
These series of checks must be carried out before
attempting any faultfinding procedures on the
appliance. On completion of any task that
required the disconnection and re-connection of
any electrical wiring or component, these checks
must be repeated.
7.8FAUL T FINDING
Before attempting any faultfinding, the electrical
checks as detailed in 7.7 must be carried out.
Isolate the appliance from the electrical supply.
Disconnect any external controls from terminals
TA & Spare of the appliance terminal strip and
make safe. Insert a solid link-wire between
terminals T A & TA.
Ensure jumper tags are fitted to the main PCB at:
● JP6
● JP7
● JP8 (Nat. Gas only).
● M7
NOTE
If the Vokera remote-control (RC05) is connected
to the appliance, it should be disconnected during
any faultfinding checks.
Restore the electrical supply to the boiler and
turn the selector switch to the on position. The
boiler should now function as described in section
7.2. Should the boiler fail to respond, the internal
fuses and connectors should be checked to
ensure integrity and continuity. If the boiler still
fails to respond, refer to the detailed faultfinding
flowcharts overleaf.
7.9FAUL T CODES
When the boiler displays a fault code, the
appropriate code is shown on the display,
accompanied by a flashing red LED. T o reset the
boiler, slowly turn the mode selector switch to
the reset position then back to the on position. If
the boiler does not reset, refer to the following
section and the detailed faultfinding flowcharts
overleaf.
FAULT CODE 01
Fault code 01 appears when the burner has failed to ignite,
or the flame supervision system has failed to detect a flame.
● Check incoming gas supply
● Check spark electrode
● Check polarity
● Check integrity of flue system
● Check gas valve
● Check ignition control PCB
FAULT CODE 02
Fault code 02 appears if the boiler has overheated.
● Check high limit thermostat
● Check thermistors
● Check pump
● Check gas pressures
FAULT CODE 03
Fault code 03 appears if the boiler or flue system has developed a fault.
● Check operation of fan
● Check flue venturi
● Check analogue pressure switch
● Check flue system
FAULT CODE 04
Fault code 04 appears if the pressure in the boiler is low.
● Check water pressure
● Check water pressure switch
● Check water pressure gauge
FAULT CODE 05
Fault code 05 appears if the appliance is connected to the
optional remote control (RC05) and there is a communication problem.
● Check wiring between RC05 and appliance
FAULT CODE 06
Fault code 06 appears if a problem exists with the secondary (DHW) thermistor.
● Check thermistor
● Check wiring continuity
FAUL T CODE 07
Fault code 07 appears if a problem exists with the primary
thermistor.
● Check thermistor
● Check wiring continuity
FAUL T CODE 08
Fault code 08 appears if the burner thermostat has been
activated.
● Check gas pressures
● Check burner thermostat
● Check wiring continuity
FAULT CODE 09
PCB fault
FAUL T CODE d1
Fault code d1 appears if the condense trap/pipe has become
blocked.
● Ensure the condense trap is clear
● Ensure the condense pipe is clear
FAUL T CODE d2
Fault code d2 appears if a problem exists with the condense
sensor.
● Check wiring continuity
● Check condense sensor
30
VOKERA
LINEA PLUS AG
Rev. 1 08/03/2000
TEST A : CHECKING OPERATION OF ELECTRONIC
CONTROL BOARD AT START UP
NO
MAINS
ON 3 WAY
NO
VALVE BETWEEN
TERMINALS
M11.1 & M11.3
ON PCB
YES
CHECK &/OR REPLACE
REPLACE PCB
WIRING OR CONNECTIONS
AND 3 WAY VALVE
IS THE
3 WAY VALVE
IN DHW
POSITION?
YES
TURN ON HOT
TAP
PUMP
RUNNING
YES
SWITCH ON/OFF
YES
START
SELECTOR TO
DHW POSITION
GREEN LED
ALIGHT
NO
A2
NO
REPLACE
CONTROL
BOARD
REPLACE
CONTROL
BOARD
NO
THERE 5 Vdc
BETWEEN TERMINALS
M5.5 & M5.6
ON PCB
CHECK WIRING AND
CONNECTIONS OR
DHW FLOW SWITCH
ON PUMP
CONNECTOR
NO
ON PUMP
IS
YES
MAINS
M15.1 &
M15.2
YES
MAINS
YES
THERE 0 Vdc
NO
BETWEEN TERMINALS
M5.5 & M5.6
NO
NO
IS
ON PCB
YES
NO
IS
THERE 0 - 1 Vdc
BETWEEN TERMINALS
M3.11 & M3.10
ON PCB
FAN RUNNING
NO
MAINS
ON FAN
CONNECTOR
M12.1 &
M12.2
YES
REPLACE FAN
YES
A
YES
MAINS
ON FAN
NO
CHECK &/OR
REPLACE
WIRING AND
CONNECTIONS
YES
REPLACE
WIRING OR
CONNECTIONS
REPLACE PUMP
CHECK FLUE GAS TUBE,
DIFFERENTIAL ANALOG
PRESSURE SWITCH AND
WIRING OR
CONNECTIONS
REPLACE
CONTROL
BOARD
31
NO
CHECK WIRING
AND
CONNECTIONS
BETWEEN TERMINALS
YES
IS
THERE 24 Vdc
BETWEEN TERMINALS
M5.3 ON PCB & WHITE WIRE
ON HIGH LIMIT
THERMOSTAT
YES
A1
IS
THERE 24 Vdc
M5.3 AND M3.3
ON PCB
NO
REPLACE THE
CONTROL BOARD
NO
RESET THE
HIGH LIMIT
THERMOSTAT
GREEN LED
LIGHT
YES
REST AR T THE
TEST
IS
THERE 24 Vdc
BETWEEN TERMINALS
M5.3 ON PCB & RED WIRE
ON HIGH LIMIT
THERMOSTAT
YES
IS
THERE 24 Vdc
BETWEEN TERMINALS
M5.3 AND M3.4
ON PCB
NO
CHECK WIRING AND
CONNECTIONS
NO
CHECK WIRING AND
CONNECTIONS,
HIGH LIMIT
THERMOSTAT OR
PCB
YES
IS
THERE 24 Vdc
BETWEEN TERMINALS
M5.3 AND M3.5
ON PCB
NO
CHECK
COMBUSTION AND
CHECK &/OR
REPLACE BURNER
THERMISTOR AND
WIRING
YES
REPLACE THE
CONTROL BOARD
32
A2
IS
RED LED
FLASHING
NOYES
SHOWING
FAULT
CODE
YES
NO
5 Vdc
BETWEEN TERMINALS
M2.1 & M2.2 ON DISPLAY
BOARD
NO
5 Vdc
BETWEEN
TERMINALS
M9.1 & M9.2 ON
CONTROL
BOARD
NO
YES
REPLACE DIGITS
BOARD
YES
CHECK AND/OR
REPLACE WIRING
OR CONNECTIONS
WITH DISPLAY BOARD
FAULT
CODE 01
SHOWING
FAULT
CODE 02
SHOWING
REPLACE THE
BICOULORED
LED ASSEMBLY
YES
NO
BICOULORED
LED ASSEMBLY
OK
YES
REPLACE THE
DIGITS BOARD
YES
SWITCH ON/OFF
SELECTOR TO
OFF POSITION
SWITCH MODE
SELECTOR TO
DHW POSITION
MAINS
PRESENT BETWEEN
M16.L & M16.N ON
CONTROL
BOARD
NO
RECHECK SUPPLY FUSE
& CONNECTORS TO
BOILER TERMINALS
REPLACE
CONTROL
BOARD
YES
YES
CHECK FUSES
F1 AND F2 ON
CONNECTION
BOARD
FUSE OK
NO
REPLACE FUSE
REST AR T THE
NO
HIGH LIMIT STAT
A4
GREEN LED
NO
CHECK WIRING AND
CONNECTIONS ,HIGH
LIMIT THERMOST . AND
CONTROL BOARD
LIGHT
GREEN LED
LIGHT
YES
YES
REST AR T THE
TEST
NO
IGNITION
CONTROL OK
NO
REPLACE
IGNITION
CONTROL
REST AR T THE
TEST
YES
REPLACE
CONTROL
BOARD
33
VOKERA
LINEA PLUS AG
Rev. 1 08/03/2000
TEST B : CHECK CONTROL
IN DHW MODE
NO
START
TURN MODE
SELECTOR SWITCH TO
DHW.
DHW STAT AT MAX.
TURN ON TAP
DOES
BURNER
LIGHT
CHECK BOILER
STARTUP:
TEST A
YES
IS
THERE A
VOLTAGE >4 Vdc
BETWEEN TERMINALS
M3.10 & M3.11
ON PCB
YES
TURN DHW
THERMOSTAT AT
MIN.
NO
IS
FAN
ON?
YES
IS
D.A.P.S.
OK?
YES
CHECK FLUE
VENTURI TUBE
NO
CHECK FAN, WIRING
AND CONNECTIONS,
DIFFERENTIAL ANALOG
PRESSURE SWITCH AND
CONTROL BOARD
NO
REPLACE DIFFERENTIAL
ANALOG PRESSURE
SWITCH
34
BURNER AND FAN
DO
SWITCH OFF
YES
TURN DHW
THERMOSTAT AT
MAX.
B
NO
IS
WATER FLOW
TEMPERATURE
>40 ˚C
YES
REPLACE
CONTROL
BOARD
WAIT WATER
FLOW
TEMPERATURE
>40 ˚C
NO
YES
START
SWITCH ON BOILER
AND SELECT MODE
TO WINTER C/H
THERMOSTAT AT
MAX.
MAKE A LINK
BETWEEN PIN M16.TA
AND M16.TA ON
CONTROL BOARD
IS THE
3 WAY VALVE
ON CH
POSITION?
VOKERA
LINEA PLUS AGRev. 1 08/03/2000
TEST C: CHECK CONTROL
IN C/H MODE
NO
DOES
BURNER
LIGHT
NO
CHECK BOILER
STARTUP
TEST A
YES
IS
THERE A
VOLTAGE >4 Vdc
BETWEEN TERMINALS
M3.10 & M3.11
ON PCB
YES
TURN CH
THERMOST AT TO
MIN.
YES
CHECK &/OR
REPLACE 3
WAY VALVE
NO
VENTURI TUBE
PRESENT BETWEEN
M11.1 & M11.2 ON
IS
FAN
ON?
YES
IS
D.A.P.S.
OK?
YES
CHECK FLUE
MAINS
CONTROL
BOARD
NO
CHECK FAN, WIRING
AND CONNECTIONS,
DIFFERENTIAL ANALOG
PRESSURE SWITCH AND
CONTROL BOARD
NO
REPLACE DIFFERENTIAL
ANALOG PRESSURE
SWITCH
NO
REPLACE
CONTROL
BOARD
BURNER AND FAN
DO
SWITCH OFF
YES
TURN CH
THERMOSTAT AT MAX.
C
NO
WATER FLOW
TEMPERATURE
>40 ˚C
REPLACE
CONTROL
WAIT WATER FLOW
TEMPERATURE
>40 ˚C
IS
NO
YES
BOARD
35
A
END
REPLACE
IGNITION
CONTROL
NO
YES
SPARK AT
ELECTRODE
YES
IGNITION
YES
LOCKOUT
AFTER
IGNITION
YES
CHECK SENSING
ELECTRODE
AND LEAD
SENSING
ELECTRODE
AND LEAD
OK
NO
REPLACE
SENSING
ELECTRODE
AND LEAD
NO
REPLACE
IGNITION
CONTROL
NO
NO
IGNITION
CONTROL
OK
YES
IS
THERE MAIN
BETWEEN TERMINALS
M14.1 & M14.2
ON PCB
NO
IS
THERE 0 Vdc
BETWEEN TERMINALS
M5.3 & M5.4
ON PCB
YES
YES
IS
THERE MAIN
BETWEEN TERMINALS
L & N ON
IGNITION
CONTROL
CHECK WIRING
YES
CHECK SPARK
ELECTRODE AND
LEAD OR REPLACE
IGNITION
CONTROL
NO
0 VDC
ON BOILER
FLOW
SWITCH
CHECK WIRING
NO
CONNECTIONS
NO
AND
CONNECTIONS
YES
AND
36
YES
CHECK WIRING
AND
CONNECTIONS
NO
REPLACE
GAS VALVE
IS
THERE A
VOLTAGE > 0.5 Vdc
BETWEEN TERMINALS
M3.11 ON PCB & GRAY
WIRE ON D.A .P.
SWITCH
GAS
VALVE
OK
YES
CHECK GAS
NO
NO
CHECK THE FAN,
VENTURI
AND/OR D.A.P.S
IS
THERE A
VOLTAGE > 0.5 Vdc
BETWEEN TERMINALS
M3.11 & M3.10
ON PCB
YES
A1
FLOW
SWITCH
OK
NO
A3
YES
CHECK WATER
A4
FAULT CODE
SHOWING 03
YES
A3
DOES THE
FLOW SWITCH PIN
OPERATE
NO
NO
FAULT CODE
SHOWING 04
NO
FAULT CODE
SHOWING 06
NO
FAULT CODE
SHOWING 07
NO
YES
REPLACE
CONTROL BOARD
YES
CHECK DHW
NTC SENSOR OR
CONNECTION
YES
NTC SENSOR OR
CHECK FLOW
CONNECTION
YES
DO
THE BOILER
FLOW SWITCH
OPERATE
YES
CHECK THE
WIRING AND/OR
THE CONTROL
BOARD
CHECK AND/OR REPLACE THE
DIAPHRAGM.
CHECK THE CORRECT WATER DP
CHECK THE WATER CIRCUIT.
CHECK IF THE PUMP IS ON 3a SPEED
NO
CHECK/
REPLACE THE
BOILER FLOW
SWITCH
FAULT CODE
SHOWING 08
NO
FAULT CODE
SHOWING d1
NO
FAULT CODE
SHOWING d2
NO
YES
YES
YES
CHECK COMBUSTION
AND BURNER
THERMISTOR OR
CONNECTION
CHECK CONDENSATE
LEVEL, SENSOR
OR WIRING
CHECK CONDENSATE
SENSOR
AND WIRING
REPLACE
CONTROL BOARD
37
C
WAIT WATER
FLOW
TEMPERATURE
< 80 ˚C
YES
BURNER AND FAN
DO
SWITCH ON
NO
WAIT 3 MIN.
DO
BURNER AND FAN
SWITCH ON
NO
IS
WATER FLOW
TEMPERATURE
>80 ˚C
NO
REPLACE
CONTROL
BOARD
REPLACE
CONTROL
BOARD
YES
YES
YES
NO
VOLTAGE < 1 Vdc
BETWEEN TERMINALS
M3.10 & M3.11
IS
TIMER JUMPER
ON
IS
THERE A
ON PCB
YES
REMOVE
JUMPER
REST AR T THE
TEST
NO
IS
THERE A
VOLTAGE >4 Vdc
BETWEEN TERMINALS
M3.10 & M3.11
ON PCB
YES
NO
REMOVE THE LINK
BETWEEN PIN M16.TA
AND M16.TA ON
CONTROL BOARD
WAIT 30 SEC.
BURNER,
YES
FAN AND PUMP
SWITCH
DO
OFF
YES
TIMER JUMPER
ON JP9
REMOVE
JUMPER
REPLACE
CONTROL
BOARD
RESTART
THE TEST
NO
CHECK FAN, WIRING
AND CONNECTIONS,
DIFFERENTIAL ANALOG
PRESSURE SWITCH AND
CONTROL BOARD
NO
IS
NO
IS
FAN
ON?
YES
IS
D.A.P.S.
OK?
38
END
NO
C1
REPLACE DIFFERENTIAL
ANALOG PRESSURE
SWITCH
YES
CHECK FLUE
VENTURI
SECTION 8WIRING DIAGRAMS
8.1EXTERNAL WIRING
The appliance comes with a factory fitted link to
allow basic operation of the boiler via the mode
selector switch. If external controls are to be
added to the system, they must be connected to
the appliance as shown in the following diagrams.
For advice on controls that are not featured in
this book, please contact Vokera technical on
0870 333 0520.
controls only the functions of the appliance
(Heating & DHW temperature, reset function,
fault code display , etc).
● Boiler control with room thermostat
function: whereby the RC05 controls the
functions of the appliance (Heating & DHW
temperature, reset function, fault code display ,
etc) and also functions as a room thermostat.
● Boiler control with programmable room
thermostat: whereby the RC05 controls the
functions of the appliance (Heating & DHW
temperature, reset function, fault code display ,
etc), and also functions as a programmable
room thermostat.
NOTE
If the RC05 is used in the “boiler only” mode, an
additional control will be required to switch
terminals T A & TA.
Full details of the operation of the RC05 and its
functions can be found in the installations and
users instructions of the RC05.
8.5VOKERA ROOM THERMOST A T
Connect the Vokera room thermostat to the
appliance as detailed in fig. 48
The Vokera room thermostat can be used with
the Vokera time clock or any other voltage-free
time clock.
Fig. 47
8.2TYPICAL CONTROL APPLICATIONS
The appliance can be used with the following
controls:
● Vokera mechanical clock (part no. 201).
● Vokera digital clock (part no. 202).
● Vokera room thermostat (part no. 011).
● Vokera RC05 remote control (part no. 405).
● Vokera external sensor (must be used in
conjunction with the RC05). (Part no.
2359259).
● Single-channel, voltage-free time clocks.
● Programmable room thermostats.
In addition, the appliance can be used in
conjunction with a typical ‘S’-Plan system, please
contact Vokera technical for further detailed
instruction.
NOTE
This appliance is not suitable for use with ‘Y’Plan systems.
8.3VOKERA TIME CLOCK
See 4.7.4 for detailed instructions on fitting the
Vokera time clock.
8.4VOKERA REMOTE CONTROL
The RC05 remote control must be connected to
the appliance as shown in fig. 47. The RC05 can
be used in 3-modes:
● Boiler only control: whereby the RC05
Fig. 48
8.6OTHER CONTROLS
Fig. 49 details typical control applications that are
suitable for this appliance. Contact the controls
manufacturer and/or Vokera technical department
should you require more specific information on
the suitability of a particular control.
Further guidance on the recommended practice
for the installation of external controls, can be
found in CHeSS – HC1/HC2 (www.energyefficiency.gov.uk).
39
Appliance wired to basic voltage-free time clock
red-black
black
blue
white-red
red-black
black
blue
white-red
Appliance wired to basic voltage-free time clock and room thermostat
Fig. 49
40
Appliance wired to programmable room thermostat
Basic wiring with link between TA & TA (no controls fitted)
FUNCTIONAL DIAGRAM
CONTROL SWITCHING OF TIME CLOCK AND ROOM THERMOSTAT IS 230 V.a.c.
NOTE: L-N-E CONNECTION IS ADVISABLE
R.T.Room thermostat
TS HHeat time switch
G.V.Gas valve
C.S.Condensate sensor
D.H.W.F.S.Domestic hot water flow switch
P.S.Water pressure switch
H.L.T.Hight limit thermostat
H.T.Heat thermistor
D.H.W.T.Domestic hot water thermistor
MODModulator
FFan
PPump
3W3 way motor
S.S.E.Spark\Sense electrode
OPEGas valve solenoids
B.C.B.
(ACF02X)Burner control board
B.E.B.Boiler control board
S.B.Secondary board
JP6Pre-heating jumper
JP7Room thermostat or remote control jumper
JP8Natural gas or L.P.G. selector
JP9Timer on- off selector
PT1 (S.B.)Selection of 0-reset / winter - summer
PT2Central heating temperature control
PT3DHW temperature control
DS1
÷DS2Temperature / alarm display
TA1Combustion test
F1Fuse 100 mA F (on 24V circuit)
F2Fuse 2 A F (on 230 V circuit)
RL1Ignition relay
RL2Pump relay
RL33 way relay
IS01Fan triac
L1Led OK (green)
L2Led alarm (blink red)
TRF1Transformer
D.A.P.S.Differential analogue pressure switch
B.T.Burner thermostat
41
WIRING DIAGRAM
Syntesi 25
Syntesi 29
Syntesi 35
NOTE: L-N-E CONNECTION IS ADVISABLE
CONTROL SWITCHING OF TIME CLOCK AND ROOM THERMOSTAT IS 230 V.a.c.
1Combustion chamber assemblyR6027R6028R10020514
2Combustion chamber back panelR5270R5316R10020518
3Combustion chamber lateral panelR5271R5271R5271
4Combustion chamber front panelR5269R5315R10020517
7Hood assemblyR10024310R10024125R10024473
10FanR10024035R10024035R10024035
13Venturi and pressure tube kitR01005293R01005293R01005293
16Clamp for tubeR10024126R10024126R10024126
19Fan flue connectionR10024137R10024137R10024137
20Block with combustion analysis checkR8085R8085R8085
23Brass capR8086R8086R8086
25Pressure differential switchR2677R2677R2677
295Silicone tubeR1457R1457R1457
300Combustion - fan cableR10024314R10024120R10024522
48
SECTION 10 LPG INSTRUCTIONS
10.1 RELATED DOCUMENTS
BS 6798INSTALLATION OF BOILERS OF RA TED NOT EXCEEDING 60kW
BS 5449PART 1FORCED CIRCULATION OF HOT W ATER SYSTEMS
BS 5546INSTALLATION OF GAS HOT WATER SUPPLIES FOR DOMESTIC PURPOSES
BS 5440PART 1FLUES
BS 5482PART 1DOMESTIC BUTANE & PROPANE GAS BURNERS IN PERMAMENT DWELLINGS
10.2
Gas Pressures252935
Inlet pressure (G31)37 mbar
Burner pressure maximum35.5 mbar35.5 mbar35.4 mbar
Burner pressure minimum6.1 mbar4.5 mbar3.4 mbar
Maximum gas rate1.94kg/h2.25 kg/h2.72 kg/h
Minimum gas rate0.77 kg/h0.77 kg/h0.77 kg/h
Injector size (quantity)12 x 0.75 mm14 x 0.75 mm16 x 0.77 mm
Flue details (concentric)
Max horizontal flue length (60/100mm)5.75m3.75m0.75m
Max vertical flue length (60/100mm)6.55m4.55m1.55m
Max horizontal flue length (80/125mm)13.80m11.80m6.75m
Max vertical flue length (80/125mm)15.30m13.30m8.25m
Efficiency
SEDBUK (%)90.789.890.5
10.3CONVERTING THE APPLIANCE GAS TYPE
T o convert the appliance to another gas type it is
necessary to change the burner injectors and
adjust the gas pressures. It is also necessary to
ensure the jumper tag at JP8 is enabled or
disabled according to the gas type used.
● To change the injectors see 6.15
● For correct jumper tag configuration see 7.8
10.4GAS SUPPLY
The gas supply must be connected to the
appliance by a competent LPG installer and must
be of sufficient size to supply the appliance at its
maximum output.
An existing supply must be checked to ensure
that it is of adequate size to deal with the
maximum rated input of this and any other
appliances that it serves.
10.5GAS SUPPLY INSTALLA TION
The entire installation including the meter must
be purged and checked for gas soundness.
10.6CHECKING AND ADJUSTING BURNER PRES-
SURE (see fig. 16)
Isolate the appliance from the electrical supply
and attach a suitable manometer to the gas valve
outlet test point.
10.6.1 SETTING THE MAXIMUM BURNER PRES-
SURE (see fig. 44)
Light the boiler as described in 5.7, fully open a
DHW outlet (preferably the bath) and ensure the
HW temperature selector is set at maximum.
Allow the appliance to stabilise.
Compare the reading on the manometer with the
value described in 10.2. If adjustment is required,
remove the protective cap from the gas valve
modulating coil assembly and turn the outer
(10mm) nut clockwise to increase, or counterclockwise to decrease the burner pressure.
10.6.2 SETTING THE MIMIMUM BURNER PRESSURE
(see fig. 45)
Once the maximum burner pressure has been
checked and/or adjusted, remove one of the grey
wires from the modulating coil. Compare the
reading on the manometer with the value
described in 10.2. If adjustment is required, turn
the inner (red) crosshead screw clockwise to
increase, or counter-clockwise to decrease the
burner pressure, whilst ensuring that the outer
(10mm) nut does not move. When checking and/
or adjustment has been completed, isolate the
appliance from the electrical supply, close the
DHW outlet, replace the protective cap, refit the
grey wire to the modulating coil, remove the
manometer, and tighten the outlet test point.
IMPORTANT, A GAS SOUNDNESS CHECK
MUST BE CARRIED OUT.