Baxi Solo 2 60 RS User guide

Please leave these instructions with the user
Baxi Solo 2 RS Range
Wall Mounted Room Sealed
Gas Fired Central Heating Boilers
Comp Nº 232184 - Iss 11 - 6/00
Installation and
Servicing Instructions

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Page 2
Natural Gas
Baxi Solo 2 60 RS
G.C. No. 41 077 79
Baxi Solo 2 50 RS
G.C.No. 41 077 78
Baxi Solo 2 40 RS
G.C.No. 41 077 77
Baxi Solo 2 30 RS
G.C. No. 41 077 76

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Page 3
Baxi UK Limited is one of the leading manufacturers of
domestic heating products in the U.K.
Our first priority is to give a high quality service to our
customers. Quality is built into every Baxi product - products
which fulfil the demands and needs of customers, offering
choice, efficiency and reliability.
To keep ahead of changing trends, we have made a
commitment to develop new ideas using the latest
technology - with the aim of continuing to make the products
that customers want to buy.
Baxi is also the largest manufacturing partnership in the
country. Everyone who works at the company has a
commitment to quality because, as shareholders, we know
that satisfied customers mean continued success.
We hope you get a satisfactory service from Baxi. If not,
please let us know.
Baxi is a BS-EN ISO 9001
Accredited Company

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Contents - Page 4
Introduction PAGE 5
Technical Data PAGE 6 - 7
System Details
(and By-pass Requirements) PAGE 8 - 11 Water Circulating Systems
System Controls
Pipework
Fully Pumped, Open Vented Systems
Low Head Installation
Sealed Systems
Gravity Systems
Hydraulic Charts
Site Requirement PAGE 12 - 14
Location
Clearances
Flue Position
Flue Dimensions
Ventilation of Compartments
Gas Supply
Electrical Supply
Installation PAGE 15 - 25
Initial Preparation
Flue Preparation
Fitting the Wall Mounting Plate
Fitting the Flue Duct
Terminal Guard
Fitting a Terminal Guard
Fitting the Boiler
Water Connections
Pipe Routes
Fully Pumped System
Sealed System
Gravity Hot Water System
Gas Connection
Electrical Supply
Commissioning the Appliance PAGE 26 - 27
Fitting the Outer Case PAGE 28
Overheat Cut-Off Device PAGE 29
Annual Servicing PAGE 30 - 32
Dismantling the Boiler
Cleaning the Burner/Injectors
Cleaning the Combustion Box
Changing Components PAGE 33 - 40
Eco Interrupter Leads
Piezo Igniter
Solenoid Operator
Thermocouple
Spark Electrode & Lead
Pilot Injector
Pilot Bracket & Gasket
Overheat Thermostat
Main Thermostat
Pump Overrun Timer
Removal of Combustion Chamber Door
Burner and Injectors
Gas Valve
Insulation Panels
Fault Finding PAGE 41
Short Parts List PAGE 42

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Introduction - Page 5
Description
The Baxi Solo 2 RS is a wall mounted gas fired room sealed
natural draught central heating boiler with range rated
outputs as shown in the table below.
Each appliance is preset at its MAXIMUM heat input rating
and is designed for use on NATURAL GAS only. They are
suitable for gravity domestic hot water with pumped central
heating, fully pumped open vented central heating and
domestic hot water and sealed systems.
The standard flue assembly supplied is suitable for wall
thicknesses between 100mm (4in) and 356mm (14in). An
optional flue extension kit is available for walls of 356mm
(14in) and 610mm (24in) thickness.
The appliance data badge is fitted to the combustion
chamber door above the gas valve.
“Benchmark” Log Book
As part of the industry-wide “Benchmark” initiative all
Baxi boilers now include an Installation,
Commissioning and Service Record Log Book. Please
read the Log Book carefully and complete all sections
relevant to the appliance and installation. These
include sections on the type of controls employed,
flushing the system, burner operating pressure etc. The
details of the Log Book will be required in the event of
any warranty work. Also, there is a section to be
completed at each subsequent regular service visit.
Installation
The installation must be carried out by a CORGI Registered
Installer and be in accordance with the relevant
requirements of GAS SAFETY (Installation and Use)
REGULATIONS, the BUILDING REGULATIONS (Scotland)
(Consolidation), the LOCAL BUILDING REGULATIONS, the
current I.E.E. WIRING REGULATIONS and the bye laws of
the LOCAL WATER UNDERTAKING. (Where no specific
instruction is given reference should be made to the relevant
BRITISH STANDARD CODES OF PRACTICE.)
B.S. Codes of Practice
STANDARD SCOPE
BS 6891 Gas Installation.
BS 5546 Installation of hot water supplies
for domestic purposes.
BS 5449 Part 1 Forced circulation hot water systems.
BS 6798 Installation of gas fired hot water
boilers.
BS 5440 Part 1 Flues.
BS 5440 Part 2 Air Supply.
WARNING
The addition of anything that may interfere with the normal
operation of the appliance (e.g. FLUE DAMPERS,
ECONOMISERS etc) without the express written permission
of BAXI could invalidate the appliance warranty and infringe
the GAS SAFETY (Installation and Use) REGULATIONS.
Important Information
This product contains Refractory Ceramic Fibres (R.C.F.)
which are man-made vitreous silicate fibres. Excessive
exposure to these materials may cause temporary irritation
to eyes, skin and respiratory tract. Care must be taken when
handling these articles to ensure the release of dust or fibres
is kept to a minimum. To ensure that the release of fibres
from these articles is kept to a minimum, during installation
and servicing it is recommended that a H.E.P.A. filtered
vacuum is used to remove any dust, soot or other debris
accumulated in and around the appliance. This should be
performed before and after working on the installation. It is
recommended that any replaced item(s) are not broken up
but sealed within heavy duty polythene bags and clearly
labelled “R.C.F. waste”. This is not classified as “hazardous
waste” and may be disposed of at a tipping site licensed for
the disposal of industrial waste. Protective clothing is not
required when handling these articles but it is recommended
that gloves are worn and the normal hygiene rules of not
smoking, eating or drinking in the work area are followed and
always wash hands before eating or drinking.

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Technical Data - Page 6
30 RS
40RS

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Technical Data - Page 7
50 RS
60RS

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System Details - Page 8
(and By-pass Requirements) Water Circulating Systems
The appliance is suitable for use with fully pumped open vented
systems (small bore and micro-bore), gravity domestic hot water
with pumped central heating systems and sealed systems.
The following conditions should be observed on all systems:
•The static head must not exceed 30m (100ft) of water.
•The boiler must only be used with an indirect cylinder.
•Drain points should be fitted to the lowest points in the
system.
•All electrical wiring, gas and water pipes must be installed
in a way which would not restrict the servicing of the boiler.
•Position isolating valves as close to circulating pump as
practicable.
•For fuel economy and best boiler performance, the system
should be designed so that gravity circulation does not take
place in the heating system when the pump is not running.
Treatment of Water Circulating Systems
For optimum performance after installation, this boiler and its
associated central heating system must be flushed in
accordance with the guidelines given in BS7593:1992
“Treatment of water in domestic hot water central heating
systems”.
This must involve the use of a proprietry cleanser, such as
BetzDearborn’s Sentinel X300 or X400, or Fernox’s Superfloc.
Full instructions are supplied with the products but for
immediate information please contact BetzDearborn on 0151
420 9563, or Fernox on 01799 550811.
For long term protection against corrosion and scale, after
flushing it is recommended that an inhibitor such as
BetzDearborn’s Sentinel X100, or Fernox’s MB-1 or Copal is
dosed in accordance with the guidelines given in BS7593:1992.
Failure to flush and add inhibitor to the system may
invalidate the appliance warranty.
BYPASS REQUIREMENTS
•The boiler is fitted with a pump overrun device which allows
the removal of residual heat from the boiler. NOTE: The pump
overrun will operate for approximately 3 minutes. The system
design must therefore always provide an open circuit for water
to circulate between the boiler flow and return.
•If a system has an open circuit a bypass is not required.
•A system using a 3 port diverter valve does not normally
require a bypass and therefore this system is recommended.
The exception to this is where all radiators in the system are
fitted with thermostatic valves, in which case a bypass would be
required. However, if one radiator in such a system was fitted
with 2 lockshield valves a bypass would not be required.
•A system controlled by non-electrical valves e.g.
mechanical thermostatic control valves both on the radiators
and the hot water circuit and systems using twin zone valves
(e.g. Honeywell ‘S’ Plan) will require a bypass.
The bypass circuit can be:-
A) A minimum of 9 metres of 22mm pipe (measured between
the boiler flow and return connections). It should be fitted with a
lockshield valve opened at least 1 full turn to give a minimum
flow rate of 8 litres/mm (1.8 gal/mm).
B) A radiator fitted with lockshield valves. The radiator output
should be a minimum of 800 watts (2,700 Btu/h). Typically a
convector type radiator with an area of 3750 cm2 (4ft2) is
adequate.
C) By including an automatic bypass valve in the system (see
diagram).
D) Any circuit that provides the same operating conditions as
option A or option B.

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System Details - Page 9
System Controls
For optimum operating conditions, the heating system into
which the boiler is installed should include a control system.
Such a system will comprise of timer control and a separate
room or cylinder thermostat as appropriate.
The boiler should be controlled so that it operates on
demand only.
Operation of the system under control of the boiler
thermostat only, does not produce the best results.
Pipework
The sizes of flow and return pipes from the boiler should be
determined by normal methods, according to the
requirements of the system.
It is recommended that the system is designed for an 11°C
(20°F) drop in temperature across the system.
In systems using non-metallic pipework it is necessary to
use copper pipe for the boiler Flow and Return. The copper
must extend at least 1 metre from the boiler and include any
branches. The copper pipe must not be insulated.
Fully Pumped, Open Vented Systems
Low Head Installation
Using a close couple arrangement the minimum head is as
shown in the diagram, subject to the following conditions:
1) The correct heat input.
2) The pump being adjusted to give an 11°C drop across
the boiler.
3) The pump must be fitted on the flow.
4) The pump must be fitted in accordance with the pump
manufacturer’s instructions.
5) The open vent pipe must be taken up from a tee in a
horizontal section of the flow pipe.
Alternative Low Head Installation for all Solo 2 RS
If less height is available then a combined vent and feed
pipe may be connected. This must be a minimum of 22mm
diameter. It is recommended that an air separator is fitted
when using a combined feed and vent pipe.

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System Details - Page 10
Sealed Systems
SAFETY VALVE
A safety valve complying with the requirements of BS 6750
Part 1 must be fitted close to the boiler on the flow pipe by
means of a horizontal or vertically upward connection with
no intervening valve or restrictions and should be positioned
to facilitate testing. The valve should be pre-set and non-
adjustable to operate at a pressure of 3 bar (45 lbf/in2). It
must be arranged to discharge any water or steam through a
pipe to a safe outlet position.
PRESSURE GAUGE
A pressure gauge of minimum range 0-4 bar (0-60 lbf/in2)
with a fill pressure indicator must be fitted to the system,
preferably at the same point as the expansion vessel in an
easily visible position.
EXPANSION VESSEL
An expansion vessel complying with the requirements of BS
4814 must be fitted to the system by means of a connection
close to the inlet side of the circulating pump in accordance
with the manufacturers instructions, the connecting pipe
being unrestricted and not less than 15mm (½ in) nominal
size. The volume of the vessel should be suitable for the
system water content and the nitrogen or air charge
pressure should not be less than the system static head.
Further details of sealed system design can be obtained
from BS 5449: Part 1 and the British Gas publication entitled
‘Specifications for Domestic Wet Central Heating Systems’.
FILLING POINT
A filling point and an approved stop valve to BS 1010 must
be fitted at low level and the method used for filling the
system should be approved by the local water undertaking.
For further details see BS 6798.
A method of replacing water lost from the system should be
provided either by means of a make up vessel of not more
than 3 litres (5 pints) capacity, mounted above the highest
point of the system, or by pre-pressurisation of the system.
A method of venting the system during filling and
commissioning must be provided by fitting automatic air
vents or by venting manually.
The hot water storage vessel must be of the indirect coil
type. All components used in the system must be suitable for
operation at 11 0°C (230°F) and at the pressure allowed by
the safety valve.

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System Details - Page 11
Gravity Systems
When the boiler is to be installed to an existing or new
gravity domestic hot water and pumped central heating
system, the following considerations should be given to the
design of the gravity domestic hot water flow and return
pipes.
The minimum circulating head should not be less than 1m
(3ft) with a maximum horizontal run of 3m (10ft) when using
28mm pipes. Smaller pipe sizes and longer horizontal runs
are acceptable with suitably increased circulating heads.
The system must be designed to prevent reverse circulation.
Pipes should be laid to maximum fall avoiding points of
possible air lock.
If the domestic hot water temperature is controlled by a
cylinder thermostat and zone valve, it is recommended that a
bypass is installed in the gravity circuit. One method is to
install a bathroom radiator, fitted with two lock shield valves.
Mechanical valves which allow the boiler to operate when
the valve is closed should not be used.
Note: If the above conditions cannot be met, then pumped
primaries must be used.
See page 25 for wiring of boiler when installed with gravity
hot water.
Hydraulic Charts

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Site Requirements - Page 12
Location
The appliance may be fitted to any suitable wall with the flue
passing through an outside wall and discharging to
atmosphere in a position permitting satisfactory removal of
combustion products and providing an adequate air supply.
The appliance should be fitted within the building unless
other-wise protected by a suitable enclosure ie. garage or
outhouse. The appliance may be fitted inside a cupboard
provided that ventilation requirements and combustible
material standards are adhered to.
If the appliance is fitted in a room containing a bath or
shower reference must be made to the Current I.E.E. Wiring
Regulations and Building Regulations. If the appliance is to
be fitted into a building of timber frame construction then
reference must be made to the current edition of Institute of
British Gas Engineers Publication IGE/UP/7 (Gas
Installations in Timber Framed Housing).
Recommendations for flues are given in BS 5440 Pt1.
Clearances
A flat vertical area is required for the installation of the boiler
measuring as shown. A space above the boiler should also
be left clear as indicated by the dotted lines.
These dimensions include the necessary clearances around
the appliance for case removal, spanner access and air
movement. Additional clearances may be required for the
passage of pipes around local obstructions such as joists
running parallel to the front face of the appliance.
If fitted inside a cupboard the clearance of 300mm shown is
only necessary when the cupboard door is open. A
clearance of 5mm (3/16 in) is required from the front of the
casing when the door is closed.
NOTE: On gravity applications a clearance of 80mm (31/8in)
is required from the top panel.
Flue Position
The following guide lines indicate the general requirements
for siting balanced flue terminals.
If the terminal is fitted within 1 metre (39in) of a plastic
gutter, within 500mm (19½ in) of a painted eave or a painted
gutter, an aluminium shield of at least 1 metre (39in) long
should be fitted to the underside of the gutter or painted
surface. An air space of 5mm (3/16 in) should be left between
shield and gutter.
If the terminal discharges onto a pathway or passageway,
check that combustion products will not cause a nuisance
and that the terminal will not obstruct the passageway.
If the outer surface of an outside wall is of combustible
material, it should be protected by fitting a non-combustible
plate so that it extends not less than 50mm (2in) around the
terminal.

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Site Requirements - Page 13
WARNING
If a terminal is less than 2 metres (78¾ in) above a balcony,
above ground or above a flat roof to which people have
access then a suitable terminal guard must be provided.
Terminal Position with Minimum Distance mm
ADirectly below an openable window or other opening,
e.g. an air brick. 300
BBelow gutters, soil pipes or drain pipes. 300
CBelow eaves. 300
DBelow balconies or car port roof 600
EFrom vertical drain pipes and soil pipes. 75
FFrom internal or external corners. 600
GAbove ground, roof or balcony level. 300
HFrom a surface facing a terminal. 600
IFrom a terminal facing a terminal. 600
JVertically from a terminal on the same wall. 1500
KHorizontally from a terminal on the same wall. 300
LFor an opening in a car port (e.g. door, window) into a
dwelling. 1200
Flue Dimensions
Recommendations for flues are given in BS 5440:1.
The standard flue terminal supplied with the appliance is
suitable for use with wall thickness between 100mm (4in)
and 356mm (14in).
A flue terminal extension kit is available as an optional extra
for wall thickness between 356mm (14in) and 610mm (24in)
from the manufacturer. Quote appliance Model N° when
ordering.

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Site Requirements - Page 14
Ventilation of Compartments
Where the appliance is installed in a cupboard or
compartment, air vents are required (for cooling purposes) in
the cupboard or compartment at high and low level which
may communicate with a room or direct to outside air.
Detailed recommendations for air supply are given in BS
5440: Part 2.
An existing cupboard or compartment may be used,
provided that it is modified for the purpose.
Recommendations for air supplies and details of essential
cupboard compartment design are given in BS 5440: Part 2.
NOTE: Both air vents must communicate with the same
room or both be on the same wall to outside air.
Gas Supply
The gas installation should be in accordance with BS 6891.
The connection on the appliance is RC½ (½ in BSPT
internal) located at the bottom right hand side of the
appliance.
Ensure that the pipework from the meter to the appliance is
of adequate size. Do not use pipes of a smaller diameter
than the appliance gas connection.
Electrical Supply
External wiring must be correctly earthed, polarized and in
accordance with CURRENT I.E.E. WIRING REGULATIONS.
The mains supply is 230V ~ 50Hz fused at 3A. NOTE: The
method of connection to the electricity supply must facilitate
complete electrical isolation of the appliance, preferably by
the use of a fused three pin plug and unswitched shuttered
socket outlet, both complying with the requirements of BS
1363.
Alternatively, connection may be made via a fused double-
pole isolator with a contact separation of a least 3mm in all
poles and serving the appliance and system controls only.

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Installation - Page 15
Initial Preparation
Unpack the contents of carton leaving the combustion box
and mounting plate assembled on the base tray. Place the
outer case in a safe place until required. Detach the fixing
template from the packaging.
Remove the two wing nuts securing the combustion box to
the mounting plate.
Disengage the spring latch and lift the combustion box away
from the airbox. Place the combustion box on its back.
Choose a flat vertical area to position the boiler, making
necessary allowances for required minimum clearances. If
fitting between wall cupboards ensure that the minimum
available width is as shown.
Hold the wall template against the wall at the required boiler
location. Ensure that the top of the template is level. The
template represents the outer limits of the appliance, plus
the required minimum clearances.
NOTE: On gravity applications a clearance of 80mm (31/8in)
is required from the top panel.
If fitting the appliance between or adjacent to kitchen wall
units, ensure that the line on the template indicating the
lower edge of the boiler is level with the lower edge of the
units and is correctly spaced.
If fitting the appliance in a compartment or cupboard with
suitable air vents (see Ventilation of Compartments), ensure
that the bottom edge of the template is level with the lower
edge of the units and is correctly spaced.
Two holes are provided on the template to allow gas and
electrical supplies to be brought directly into the boiler from
the wall. The grommet provided must be used when the
electrical cable is routed through the wall mounting plate.
Mark the position of the flue hole and four good anchorage
points. Where possible use the uppermost and lowest fixing
hole positions, otherwise space the fixing holes as far apart
as possible. Mark gas and electrical supply access holes if
required. Cut out hole for flue. Drill anchorage holes 7mm
(9/32 in) diameter by 63mm (2½ in) deep to accept wall plugs.

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Installation - Page 16
Flue Preparation
Unpack flue duct, flue trim and air duct.
Measure overall wall thickness. If this is between 280mm (11
in) and 355mm (14in), use flue as supplied without
alteration.
For wall thickness between 102mm (4in) and 280mm (11 in),
air duct and flue duct are required to be shortened.
Using the indication on the duct, mark accordingly to table
below.
Bend tabs as shown.
Using tin snips, cut around ducts at appropriate mark.
Remove any sharp edges.

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Installation - Page 17
Fitting the Wall Mounting Plate
Secure plate to wall using 63mm (2½ in) screws.
From outside building, pass air duct through wall opening. The
two tabs should be positioned at the bottom.
Slide air duct over inner duct until tabs contact wall surface.
Ensure air duct is horizontal and square to wall face. Using
sealing tape supplied make good the joint on inside of the two
ducts.
Make good with cement mortar between the outside wall and
duct.

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Installation - Page 18
Fitting the Flue Duct
Fit flue trim over air duct.
Slide flue duct inside air duct to
engage flue duct on boiler, noting
correct positioning as labelled.
Secure flue duct, flue trim to air duct with four screws
provided in the kit.
Remove label from duct.

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Installation - Page 19
Terminal Guard
When codes of practice dictate the use of terminal guards,
they can be obtained from most plumbers and builders
merchants nationwide.
When ordering a terminal guard, quote the appliance model
number.
The guard manufacturers listed below can be contacted for
terminal sizes and guard model numbers.
Quinnell, Barrett & Quinnell,
884 Old Kent Road,
London, SE15 1NL.
Tel: [phone].
Tower Flue Components Ltd.,
Tower House,
Vale Rise,
Tonbridge,
Kent.
Tel: [phone]
Fitting a Terminal Guard
Position the guard over the terminal on the outside. wall.
Ensure guard is equally spaced about terminal. Mark fixing
positions.
Drill and plug fixing positions, then secure guard to wall.

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Installation - Page 20
Fitting the Boiler
When the boiler is to be used on a system with gravity
D.H.W. it is necessary to disconnect the overheat thermostat
by removing the wire with the black sleeve and attaching it to
the wire with the red sleeve as shown.
The overheat thermostat is now by-passed and will allow the
appliance to perform satisfactorily on gravity circulation.
NOTE: Even though the overheat thermostat is not
operational, it must not be removed from the pocket in the
heat exchanger except during servicing.
Lift boiler and engage centrally the back bottom edge into
the hook bracket on the mounting plate.
Rotate the boiler back to the mounting plate to engage two
studs and spring latch.
Fit the two wing nuts. Tighten to compress rear flue seal.