Buderus Logano plus SB745 User manual

For users
Read carefully before use
Operating instructions Floor standing
condensing boiler
Logano plus SB745
6 720 648 053-00.2T
Output range 800 – 1200 kW
6 720 800 395 (2012/03) GB

Introduction
Logano plus SB745 - Subject to technical modifications
2
Introduction
Dear Customer,
Heat is our element – and has been now for more than
275 years. Right from the start, we invest all our energies
and passion into developing individual solutions for you,
so you feel comfortable in your home.
Whether heat, domestic hot water or ventilation, a
product from Buderus will always provide you with highly
efficient heating technology of proven quality that will
reliably keep your home cosy for many years to come.
We manufacture in accordance with the state of the art
and ensure that our products are efficiently matched to
each other. In this endeavour, efficiency and
environmental compatibility are our priorities.
Thank you for choosing a Buderus product – a choice that
will give you not only efficient energy utilisation but also
high levels of comfort and convenience. To ensure that
you retain this level of excellence, please read the
operating instructions carefully. If, contrary to
expectations, problems arise, please contact your installer
who will be happy to assist you.
Should your installer not be available, then contact our
customer service that is available to you around the clock.
We hope you will enjoy your new Buderus product!
Your Buderus Team

Contents
Logano plus SB745 - Subject to technical modifications 3
Contents
1 Key to symbols and safety instructions . . . . . 4
1.1 Key to symbols . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Safety instructions . . . . . . . . . . . . . . . . . . . . 5
2 About the boiler . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Correct use . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 CE Declaration of Conformity . . . . . . . . . . . 6
2.3 Suitable fuels . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Data plate . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.5 Product description . . . . . . . . . . . . . . . . . . . 6
3 Information on installation and operation . . 8
3.1 Combustion air quality . . . . . . . . . . . . . . . . . 8
3.2 Heating water quality . . . . . . . . . . . . . . . . . . 8
4 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.1 Preparing the heating system for
operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.2 Commissioning the control unit
and burner . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5 Shutting down . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.1 Shutting down the heating system . . . . . . . 9
5.2 Shutting down the heating system in
an emergency . . . . . . . . . . . . . . . . . . . . . . . 9
6 Correcting a burner fault . . . . . . . . . . . . . . . . . 9
7 Inspection and maintenance . . . . . . . . . . . . . 10
7.1 General notes . . . . . . . . . . . . . . . . . . . . . . 10
7.2 Why is regular maintenance important? . 10
7.3 Checking and correcting the
water pressure . . . . . . . . . . . . . . . . . . . . . 10
7.3.1 When should you check the water
pressure in the heating system? . . . . . . . 10
7.3.2 Sealed unvented systems . . . . . . . . . . . . . 11
7.3.3 Installations with automatic
pressurisation units . . . . . . . . . . . . . . . . . . 11
8 Energy saving information . . . . . . . . . . . . . . . 12
9 Environmental protection/disposal . . . . . . . 13
10 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

1Key to symbols and safety instructions
Logano plus SB745 - Subject to technical modifications
4
1 Key to symbols and safety instructions
1.1 Key to symbols
Warnings
Keywords indicate the seriousness of the hazard in terms
of the consequences of not following the safety
instructions.
•NOTICE indicates that material damage may occur.
•CAUTION indicates that minor to medium injury may
occur.
•WARNING indicates that serious injury may occur.
•DANGER indicates possible risk to life.
Important information
Additional symbols
Warnings in this document are framed and
identified by a warning triangle which is
printed on a grey background.
Electrical hazards are identified by a lightning
symbol surrounded by a warning triangle.
Important information in cases where there is
no risk of personal injury or material losses is
identified by the symbol shown on the left. It
is bordered by horizontal lines above and
below the text.
Symbol Meaning
Ba step in an action sequence
Æa reference to a related part in the
document or to other related documents
• a list entry
–a list entry (second level)
Tab. 1

1
Key to symbols and safety instructions
Logano plus SB745 - Subject to technical modifications 5
1.2 Safety instructions
Danger through failure to consider your own safety
in an emergency such as a fire
BNever put your life at risk. Your own safety is
paramount.
If you smell gas
Bclose the gas tap.
BOpen the windows.
BNever operate electrical switches, including
telephones, plugs or door-bells.
BExtinguish all naked flames.
BNo open fire.
BNever smoke.
BNever use lighters.
BWarn all occupants of the building, but do not ring
doorbells.
BLeave the building and telephone your gas supply utility
and authorised contractor from an outside phone.
If you smell exhaust gas
BSwitch off the appliance.
BOpen windows and doors.
BNotify an authorised contractor.
Electric shock hazard
BBefore carrying out any work on the heating system,
disconnect it from the power supply across all poles.
For example, activate the emergency stop switch
outside the boiler room. It is not enough to switch off
the control unit.
BSafeguard the heating system against unintentional
reconnection.
BAdhere to country-specific rules and regulations when
making the electrical connection, commissioning,
servicing and carrying out maintenance.
Siting, conversion
An insufficient supply of air can result in dangerous
escape of flue gas.
BOnly have the boiler installed or modified by a
competent person.
BNever change any parts in contact with flue gas.
BNever cover or reduce the size of air vents in doors,
windows or walls. If draught-proof windows are fitted,
ensure there is an adequate supply of ventilation and
combustion air.
BEnsure that the boiler installation room remains free
from the risk of frost.
BThe heating system must be installed and operated in
accordance with the applicable codes of practice as
well as national, regional and local code.
Thermal disinfection
BRisk of scalding!
Monitor any operation with temperatures in excess of
60 °C.
Inspection and maintenance
BRecommendation for customers: Arrange a
maintenance and inspection contract with an
authorised contractor, covering an annual inspection
and responsive maintenance.
BThe user is responsible for the general and
environmental safety of the heating system.
BImmediately correct all faults to prevent system
damage.
BUse only original, genuine spare parts from the
manufacturer. Losses caused by the use of spare parts
and accessories not supplied by the manufacturer are
excluded from the manufacturer's warranty.
Explosive and highly flammable material
BNever use or store highly flammable materials (paper,
thinners, paints etc.) near the boiler.
Combustion/ambient air
BKeep the combustion/ambient air free of corrosive
substances (e.g. halogenated hydrocarbons that
contain chlorine or fluorine compounds). This will help
prevent corrosion.
BKeep the combustion air supply free of dust.
Disposal
BDispose of packaging in an environmentally
responsible manner.

2About the boiler
Logano plus SB745 - Subject to technical modifications
6
2 About the boiler
2.1 Correct use
The Logano plus SB745 condensing boiler has been
designed for hot water heating systems in e.g. multiple
dwelling units or for industrial use.
Any gas burner to EN 676 and EN 267 can be used if its
operating range matches the boiler specification.
Only burners that have been tested and approved for
electromagnetic compatibility (EMC) may be used.
Logamatic 4000 control units are used with these boilers.
For further details on correct use Æchapter 2.3,
chapter 2.5 and chapter 3, page 8.
2.2 CE Declaration of Conformity
The design and operation of this product conform to the
applicable European directives and supplementary
national requirements. Conformity has been
demonstrated.
The Declaration of Conformity can be viewed at
www.buderus.de or alternatively can be requested from
your local Buderus sales office.
2.3 Suitable fuels
Permissible fuels
• Natural gas from the public gas supply in accordance
with national regulations with a total sulphur content
<50 mg/m³.
• LPG in accordance with national regulations with a
content of elementary sulphur <1.5 ppm and volatile
sulphur <50 ppm.
The boiler must only be operated with the specified fuels.
Only burners that are suitable for the specified fuels may
be used.
Observe the manufacturer's burner selection list and the
burner manufacturer's instructions.
2.4 Data plate
The data plate is fitted to the back of the boiler casing.
There you will find information such as the serial number,
output and approval details.
2.5 Product description
The Logano plus SB745 is a floor standing condensing
boiler with a slim, compact design and a small footprint
thanks to the combustion chamber located at the top and
the condensation heating surface located at the bottom.
It is referred to in this manual as the SB745 or the boiler.
The SB745 has two thermo-hydraulically separated return
connections for the high and low temperature circuits.
For the type-tested boiler sizes with internal condensing
heat exchanger and CE designation, the components that
come into contact with hot gas and condensate are made
of stainless steel.
Equip the SB745 with a suitable burner.
Optional accessories can be found in the general
catalogue.
The combustion of biogas is not permitted.
If you contact the manufacturer with any
questions about this product, always provide
the details on the data plate. These details
enable us to assist you specifically and
quickly.
NOTICE: System damage through incorrect
burner.
BOnly use burners which meet the
technical boiler requirements.

2
About the boiler
Logano plus SB745 - Subject to technical modifications 7
The main SB745 components are (Æfig. 1):
• Boiler body [1] in conjunction with a burner.
The boiler block transfers the heat generated by the
burner to the heating water.
• Thermally insulating casing.
The boiler jacket and thermal insulation reduce heat
losses.
• Control unit (accessory – [8]).
The control unit monitors and controls all electrical
boiler components.
Fig. 1 Boiler overview
1Boiler body
2Combustion chamber door
3Safety lug to secure the load during transportation
(not for lifting)
4Flue gas collector
5Condensate drain, siphon
6Drain
7Base frame rail
8Control unit (accessory)
9Cable conduit
10 Flue gas connection
11 Inspection opening, reversing chamber
12 Return 1 (RK1), low temperature return
(main return)
13 Return 2 (RK2), high temperature return
14 Inspection opening on the water side (both sides)
15 Flow safety connection
16 Boiler flow
17 Valve manifold (accessory)
18 Lifting eyes
6 720 648 053-13.2T
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6
16
17
13 1412
11
10
3
4
2
1
3
7
8
9
18
15

3Information on installation and operation
Logano plus SB745 - Subject to technical modifications
8
3 Information on installation
and operation
3.1 Combustion air quality
BKeep the supply of combustion air free of corrosive
substances (e.g. halogenated hydrocarbons that
contain chlorine or fluorine compounds).
This will help prevent corrosion.
BNever use or store chlorinated cleaning agents or
halogenated hydrocarbons (as contained in spray
cans, solvents or cleaning agents, paints and
adhesives, for example) in the boiler room.
BKeep the combustion air supply free of dust.
BIf building work is taking place in the installation room
and creating a lot of dust, shut the boiler down.
A burner contaminated during building work must be
cleaned before commissioning.
3.2 Heating water quality
The quality of the fill and top-up water is essential for
increased efficiency, functional reliability, long service life
and for maintaining the constant operational condition of
a heating system. If the system is filled with water that has
a high calcium hardness, this will be deposited on the
heat exchanger surfaces and will obstruct the transfer of
heat to the heating water. As a result, the wall
temperatures of the stainless steel heat exchanger
surfaces will rise and the thermal stresses (loads on the
boiler body) will increase.
This is why the quality of the fill or top-up water must meet
the conditions stipulated in the operator's log provided
and be recorded in this log.
The conditions for boilers > 600 kW require general
water treatment independent of the water hardness and
the volume of fill and top-up water.
4 Commissioning
BAsk your contractor to provide information about how
the boiler works and is operated.
BNever undertake any modifications or maintenance.
4.1 Preparing the heating system for
operation
For you to be able to commission the heating system,
observe the following:
BCheck that the required operating pressure has been
built.
BCheck the flange connections and other connections
for tightness.
BFill the condensate siphon.
4.2 Commissioning the control unit and
burner
By commissioning the control unit you automatically
commission the burner as well. The burner can then be
started by the control unit. For further information, see the
installation instructions of the relevant control unit or
burner.
BUse the control unit to commission the boiler.
For the installation and operation of the
heating system, observe all country-specific
standards and guidelines.
The information on the data plate is binding
and must be observed.
Open the automatic air vent valve only briefly
for ventilation.

5
Shutting down
Logano plus SB745 - Subject to technical modifications 9
5 Shutting down
5.1 Shutting down the heating system
Shut down your heating system via the control unit.
Switching off the control unit automatically also switches
off the burner.
BSet the On/Off switch of the control unit to "0" (Off).
BIsolate the fuel supply to the burner.
5.2 Shutting down the heating system in
an emergency
BIn dangerous situations, immediately close the main
fuel shut-off valve and the power supply of the heating
system via the boiler room main MCB/fuse or the
heating system emergency stop switch.
BIsolate the fuel supply to the burner.
BNever put your life at risk. Your own safety is
paramount.
6 Correcting a burner fault
The display shows heating system faults. Further
information on the fault displays can be found in the
service instructions of the relevant control unit. In addition,
burner faults are signalled by an indicator on the burner.
BPress burner reset button (see burner operating
instructions).
If the burner still fails to start after three attempts, contact
a contractor.
NOTICE: Risk of system damage through
frost.
When there is a frost, the heating system can
freeze up if it is not operational, e.g. because
of a fault shutdown.
BWhen there is a risk of frost, protect your
heating system against freezing up.
BIf your heating system has been shut down
for several days due to a fault shutdown
and there is a risk of frost, drain the
heating water at the drain & fill valve. Also
leave the air vent valve at the highest point
in the system open.
NOTICE: Risk of system damage through
frost.
The heating system can freeze up as a result
of a power failure or if the power has been
switched off.
BCheck the "Control unit settings" to
ensure the system remains operational
(especially when there is a risk of frost).
Only in emergencies, switch OFF the heating
system via the boiler room MCB/fuse or the
heating system emergency stop switch.
NOTICE: Risk of system damage through
frost.
When there is a frost, the heating system can
freeze up if it is not operational, e.g. because
of a fault shutdown.
BIf your heating system has been shut down
for several days due to a fault shutdown
and there is a risk of frost, drain the
heating water at the drain & fill valve. Also
leave the air vent valve at the highest point
in the system open.
NOTICE: System damage due to the reset
button being pressed too frequently.
This can damage the burner ignition
transformer.
BPress the reset button no more than three
times in a row.

7Inspection and maintenance
Logano plus SB745 - Subject to technical modifications
10
7 Inspection and maintenance
7.1 General notes
Enter into an annual inspection and responsive
maintenance and inspection contract with your
contractor.
7.2 Why is regular maintenance
important?
Have your heating system regularly serviced:
• to maintain a high level of efficiency and to operate the
system economically (low fuel consumption)
• to achieve a high level of operational reliability
• to maintain the cleanest possible combustion.
7.3 Checking and correcting the water
pressure
The heating system must contain sufficient water to
safeguard its correct function.
BIf the water pressure in the heating system is too low,
top up with water.
BCheck the water pressure monthly.
7.3.1 When should you check the water pressure
in the heating system?
Recently added fill or top-up water loses much of its
volume in the first few days because it releases gases.
With new systems you should therefore initially check the
heating water pressure on a daily basis, and then at
gradually longer intervals.
• Once the heating system is hardly losing any volume,
check the heating water pressure monthly.
A distinction is generally made between open vented and
sealed unvented systems. In practice, open vented
systems are rarely installed nowadays. We will therefore
be using a sealed unvented heating system to
demonstrate how you can check the water pressure. All
settings will have already been made by the installation
engineer when the system was first commissioned.
NOTICE: System damage due to inadequate
cleaning and maintenance.
BCarry out cleaning and maintenance
procedures annually. In the course of this
work, check the entire heating system
including the neutralising system for
correct function.
BImmediately correct all faults to prevent
system damage.
Use only original, genuine spare parts from
the manufacturer. Spare parts can be
ordered from the manufacturer's spare parts
catalogue.
Annual inspection and service are part of the
warranty terms.
The fill and top-up water quality must comply
with the specification in the boiler log
supplied.
Air pockets may form in the heating system
through the fill or top-up water releasing
gases.
BVent the heating system (e.g. by bleeding
the radiators).
BIf required, top up with water.

7
Inspection and maintenance
Logano plus SB745 - Subject to technical modifications 11
7.3.2 Sealed unvented systems
For sealed unvented systems, the pressure gauge needle
[3] must be within the green band [2]. The red needle [1]
of the pressure gauge must be set to the pressure
required for the heating system.
BCheck the heating system water pressure.
BIf the pressure gauge needle [3] no longer lies between
the two red indicators, top up with water.
BTop up with water via the filling valve in the heating
system pipework.
BVent the heating system.
BCheck the water pressure once more.
Fig. 2 Pressure gauge for sealed unvented heating
systems
1Red needle
2Green marking
3Pressure gauge needle
7.3.3 Installations with automatic pressurisation
units
For installations with an automatic pressurisation unit
observe the manufacturer's instructions.
The water quality requirements also apply here
(Æchapter 7.3.1, page 10).
NOTICE: System damage through frequent
topping up.
Subject to the water quality, your heating
system can be damaged through corrosion
or scaling.
BEnsure that the heating system is vented
correctly.
BCheck the heating system for leaks and
the expansion vessel for functionality.
BObserve the requirements regarding
water quality (see operator's log).
BIf water loss occurs frequently, locate the
cause and rectify the problem without
delay.
NOTICE: System damage through
temperature stresses.
BOnly fill the heating system when cold (the
flow temperature must not exceed 40 °C).
BDuring operation, only fill the heating
system via the fill valve in the heating
system pipework (return).
6 720 648 053-30.1T
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2

8Energy saving information
Logano plus SB745 - Subject to technical modifications
12
8 Energy saving information
Heating economically
The appliance has been designed, so that the gas
consumption and environmental impact are as low as
possible yet comfort is at its optimum level.
Inspection/Maintenance
So that gas consumption and environmental impact can
be kept as low as possible for as long as possible, we
recommend that you take out an inspection and
maintenance contract with an approved contractor
covering an annual inspection and service subject to
demand.
Heating controls
Install the heating control unit with room temperature
controller or a weather-compensated controller and
thermostatic valves.
For further information, see the relevant installation and
operating instructions of the controller.
Heating systems with weather-compensated
control unit
With this type of control, the outside temperature is
captured, and the heating flow temperature is adjusted in
accordance with the heating curve set at the controller.
The lower the outside temperature, the higher the flow
temperature.
Set the heating curve as low as possible. Turn the
appliance temperature controller to the maximum design
temperature of the heating system.
Heating systems with room temperature-
dependent control
The room where the room temperature controller is
installed (reference room) determines the temperature in
other rooms. Thermostatic valves should not be installed
in the reference room.
Set the appliance temperature controller to the maximum
design temperature of the heating system.
In each room (except the reference room), the
temperature can be regulated individually by means of
thermostatic valves. If a lower temperature is required in
the lead room than in the other rooms, reference the room
temperature controller set as is and reduce the
temperature at the radiator valve.
Thermostatic valves
Fully open the thermostatic radiator valves in order to
achieve the required room temperature. Change the
required room temperature at the temperature controller
only if the temperature is not achieved after a prolonged
period.
Venting
Never leave windows slightly open for ventilation
purposes. Otherwise, heat will be constantly discharged
from the room without significantly improving the air
quality in the room. It is better to fully open windows
briefly.
Close thermostatic radiator valves whilst airing rooms.
Now you know how to heat economically with the heating
system. Contact your installer should you have further
questions – alternatively, write to us.

9
Environmental protection/disposal
Logano plus SB745 - Subject to technical modifications 13
9 Environmental protection/disposal
Environmental protection is key commitment for the
Bosch Group.
Quality of products, efficiency and environmental
protection are equally important objectives for us. All
legislation pertaining to the environment is strictly
observed. To protect the environment we use the best
possible technology and materials, subject to economics.
Packaging
We are dedicated to adhering to country-specific
disposal standards for packaging in order to ensure
optimum recycling. All packaging materials are
environmentally compatible and can be recycled.
Old appliance
Old appliances contain materials that should be recycled.
The relevant assemblies are easy to separate, and all
plastics are identified. This allows the various assemblies
to be appropriately sorted for recycling or disposal.

10 General
Logano plus SB745 - Subject to technical modifications
14
10 General
Cleaning the boiler jacket
Wipe down the boiler jacket with a damp cloth. Never use
aggressive or corrosive cleaning agents.
Appliance details
When requesting a customer service visit, it is useful to
provide detailed information about your appliance.
You will find these details on the data plate or the
appliance type label (Æinstallation and maintenance
instructions)
Gas boiler (e.g. Logano SB615):
.........................................................................................................
Serial number: .............................................................................
Date commissioned: ..................................................................
Correct fuel
This heating system requires the correct fuel to ensure
perfect operation. During commissioning, your heating
contractor will enter the correct fuel type for your heating
system in the table below.
NOTICE: Risk of system damage through
use of incorrect fuel.
BOnly use the fuel intended for your heating
system.
We recommend you seek the advice of your
heating contractor if you intend to change the
fuel for your heating system.
Use only the following fuel:
Stamp/Signature/Date
Tab. 2

Index
Logano plus SB745 - Subject to technical modifications 15
Index
A
About the appliance............................................................... 6
Appliance description....................................................... 6
CE Declaration of Conformity......................................... 6
Correct use ......................................................................... 6
Overview of possible fuels .............................................. 6
Appliance description............................................................ 6
C
CE Declaration of Conformity.............................................. 6
Checking and correcting the water pressure ................ 10
Commissioning
Commissioning the burner .............................................. 8
Commissioning the control unit...................................... 8
Preparing the heating system for operation ................ 8
Commissioning the burner ................................................... 8
Commissioning the control unit........................................... 8
Correct use .............................................................................. 6
D
Data plate ................................................................................. 6
Disposal .................................................................................. 13
E
Energy saving information................................................... 12
Environmental protection .................................................... 13
F
Fuels .......................................................................................... 6
I
Inspection............................................................................... 10
Inspection and maintenance
Checking and correcting the water pressure............ 10
General information......................................................... 10
K
Key to symbols ........................................................................ 4
M
Maintenance .......................................................................... 10
O
Old appliance ........................................................................ 13
Overview of Logano plus SB745 ....................................... 7
P
Packaging............................................................................... 13
Preparing the heating system for operation ..................... 8
Product description................................................................ 6
R
Recycling................................................................................ 13
S
Safety instructions................................................................... 5
Shutdown
Shutting down the heating system in emergencies.... 9
Shutting down.......................................................................... 9
Shutting down the heating system................................. 9
Shutting down the heating system...................................... 9
shutting down the heating system in emergencies ......... 9
W
Water pressure ..................................................................... 10

Buderus
Cotswold Way, Warndon, Worcester WR4 9SW
All Enquiries: 0844 892 3004
www.buderus.co.uk
In the UK and IE, Buderus is a brand name
of Bosch Thermotechnology Ltd.