Worcester GB162-50 User manual

UK/IE
User instructions
Wall hung gas-fired condensing boiler
Worcester Commercial Boiler Series
GB162-50/65/80/100
6 720 648 726-000.1TD
For central heating systems and indirect fed domestic hot water
6720813172 (2015/04)

preface
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preface
Please read these instructions carefully
These instructions are applicable to the Worcester, Bosch Group boiler
model stated on the front cover only.
These instructions apply in the UK/IE only and must be followed except
for any statutory obligation.
After installation please leave this User instruction Manual, Installation,
Commissioning and Servicing Instructions and completed Benchmark
Checklist with the user.
Dedicated to heating comfort
Thank you for purchasing a Worcester GB162 gas-fired condensing
boiler manufactured by Worcester, Bosch Group. The company prides
itself on manufacturing boilers to the strictest quality control standards
throughout every stage of production.
Worcester, Bosch group has led the field in innovative boiler design and
performance for over 50 years. This heritage means all our products are
of exceptional quality and proven reliability.
The Worcester commercial range in particular is extremely energy
efficient, offering you economical running costs and value for money.
There is also the reassurance of our no-nonsense 2 years parts and
labour guarantee.
Contents
1 Key to symbols and safety instructions . . . . . . . . . . . . . . . . . . . 2
1.1 Key to symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Energy efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4 Overview of the BC10 basic controller . . . . . . . . . . . . . . . . . . . 4
5 Service Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
6 Maintaining your Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
7 Explanation of the control unit . . . . . . . . . . . . . . . . . . . . . . . . . . 5
7.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
8 Operating the heating system . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
8.1 Menu structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
8.1.1 Normal Operation menu . . . . . . . . . . . . . . . . . . . . . . . . . . 6
8.1.2 Manual Operation menu . . . . . . . . . . . . . . . . . . . . . . . . . . 6
9 Extreme Cold Weather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
10 Display information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
10.1 Display readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
10.2 Display codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
10.2.1 Fault or Breakdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
10.3 Identifying and resetting faults . . . . . . . . . . . . . . . . . . . . 9
11 Tips on energy saving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
12 Environment / disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
13 Your Guarantee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
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
1.2 safety precautions
INTENDED USE
This boiler is only to be used to heat heating system water and for the
domestic hot water (DHW) supply e. g. in residential and light
commercial properties. It can also be integrated into a cascade system
(where several boilers are interconnected).
The boiler has been factory-fitted with the BC10 basic controller and the
“Universal Burner Automat 3” (UBA 3).
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
▶ a step in an action sequence
a reference to a related part in the document or to other
related documents
• a list entry
– a list entry (second level)
Table 1

General Information
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If you smell gas!
▶ Call the National Gas Emergency Service on:
0800 111 999
▶ Extinguish any naked flames
▶ Do not smoke or strike matches
▶ Do not turn electrical switches on or off
▶ Open doors and windows
▶ Keep people away from the affected area
▶ Turn off the gas control valve at the meter
Boiler Operation
This boiler must only be operated by a responsible adult who has been
instructed in, understands and is aware of the boiler's operating
conditions and effects.
Combustible and Corrosive Materials
Chemically aggressive substances can corrode the boiler and invalidate
any warranty.
▶ Do not store or use any combustible materials (paper, thinners,
paints etc.) inside or within the vicinity of the boiler.
Fittings and Modifications
Only a competent engineer in accordance with the Gas Safety
(Installation and Use) Regulations can remove the outer case and carry
out any work.
▶ Do not open the appliance.
Any misuse or unauthorised modifications to the boiler, flue or
associated components and system will invalidate the warranty.
▶ Do not modify the boiler or flue system in any way.
Worcester, Bosch Group accepts no liability arising from any such
actions. This does not affect your statutory rights.
CE label
The appliance complies with the basic requirements of the relevant
European directives.
Conformity has been substantiated by the proper documents which -
together with the declaration of conformity - are filed with the
manufacturer.
Abbreviations
• CH (boiler) flow = Central Heating flow
• CH return = Central Heating return
• DHW outlet = Domestic Hot Water warm outlet
• MCW inlet = Mains Cold Water inlet
• UBA 3 = Universal Burner Automat 3.
2 General Information
Servicing
▶ The boiler must be serviced regularly by a competent, qualified
person, such as a Worcester service engineer or other Gas Safe
registered engineer.
▶ Always use original spares, to help maintain the economy, safety and
reliability of the boiler and have the Service Record completed in the
Installation Checklist.
3 Energy efficiency
The following product data satisfy the requirements of the EU Regulations No. 811/2013, No. 812/2013, No. 813/2013 and No. 814/2013
supplementing Directive 2010/30/EU.
Ensure that the service engineer completes the Service
Record after each service.
The Installation Checklist and service interval record can
be found at the rear of the Installation, Commissioning
and Servicing Instructions.
Product data Symbol Unit 7736700642 7746900822 87470248 87470250
Product type – – GB162-50
G20
GB162-65
G20
GB162-80
G20
GB162-100
G20
Condensing boiler – –Yes Yes Yes Yes
Rated heat output Prated kW 47 61 82 95
Seasonal space heating energy efficiency ηs%93 92 – –
Energy efficiency class – –A A––
Useful heat output
At rated heat output and high temperature regime 1)
1) High-temperature regime means 60 °C return temperature at heater inlet and 80 °C feed temperature at heater outlet.
P4kW 46.6 60.5 82.0 94.5
At 30 % of rated heat output and low temperature regime 2)
2) Low temperature means for condensing boilers 30 °C, for low-temperature boilers 37 °C and for other heaters 50 °C return temperature (at heater inlet).
P1kW 15.4 20.1 26.6 31.6
Useful efficiency
At rated heat output and high temperature regime 1) η4% 87.3 87.3 88.2 88.4
At 30 % of rated heat output and low temperature regime 2) η1% 97.3 97.3 97.3 98.3
Auxiliary electricity consumption
At full load elmax kW 0.045 0.073 0.100 0.145
At part load elmin kW 0.021 0.019 0.024 0.027
In standby mode PSB kW 0.008 0.004 0.008 0.008
Other items
Standby heat loss Pstby kW 0.085 0.082 0.082 0.082
Ignition burner power consumption Pign kW 0.000 0.000 0.000 0.000
Emissions of nitrogen oxides NOx mg/kWh 15 36 42 49
Sound power level, indoors LWA dB(A) 54 60 – –
Table 2 Product data for energy consumption

Overview of the BC10 basic controller
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4 Overview of the BC10 basic controller
Fig. 1 BC10 basic controller
[1] Mains switch (boiler On/Off)
[2] c“Reset” button (fault reset button)
[3] dChimney sweep button (for manual operation)
[4] eService button
[5] Service Connector
[6] G“Burner LED” (On/Off)
[7] R“Heat demand” LED
[8] Maximum CH (boiler) flow temperature dial
[9] Display (for status indication)
[10] S“DHW mode” LED
[11] DHW temperature dial
5 Service Clearances
The boiler must be located in an area with the following service clearances.
Fig. 2 Clearances
6 720 648 727-001.1TD
11 10 9 8 7
65432
1
550 mm
40 mm
250 mm
(100 mm below
pump group)
0 mm 0 mm
6 720 648 727-002.1TD
Your installer will have provided adequate space around
the boiler for safety and servicing access.
CAUTION: Restricted space.
The boiler may overheat.
▶ Do not restrict this space with the addition of
cupboards, shelves etc. next to the boiler.

Maintaining your Boiler
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6 Maintaining your Boiler
Your new gas-fired boiler represents a long term investment in a reliable,
high quality product.
In order to realise its maximum working life, and to ensure it continues to
operate at peak efficiency and performance, it is essential that your
boiler receives regular servicing and maintenance checks from a
competent person beyond the initial 2 year guarantee period.
If your gas-fired boiler should fail to operate correctly or requires
servicing please contact Worcester, Bosch Group Appointments Team
(see rear cover for details).
7 Explanation of the control unit
7.1 General
The boiler is fitted with a control unit, the BC10 basic controller
(fig. 1). This controller can be used to control the heating system.
▶ Push on the control panel to open it (fig. 3).
Fig. 3 Opening the control panel
The BC10 basic controller is located on the left, behind the control
panel.
The BC10 basic controller consists of the following components:
Fig. 4 BC10 basic controller
[1] Mains switch (boiler On/Off)
[2] c“Reset” button (fault reset button)
[3] dChimney sweep button (for manual operation)
[4] eService button
[5] Service Connector
[6] G“Burner LED” (On/Off)
[7] R“Heat demand” LED
[8] Maximum CH (boiler) flow temperature dial
[9] Display (for status indication)
[10] S“DHW mode” LED
[11] DHW temperature dial
Mains switch
The mains switch (fig. 4, item 1) is used to switch the boiler on and
off.
“Reset” button
If a fault has occurred you may have to restart the boiler by pressing the
“Reset” button (fig. 4, item 2).
This is only required in the event of a “locking” fault. “Blocking” faults are
reset automatically as soon as their cause has been removed.
The display shows “rE”during the reset operation.
“Chimney sweep” button
The “Chimney sweep” button (fig. 4, item 3) is used to put the boiler
into manual operation mode, e.g. if the heating system control (e.g.
room controller) is defective.
The heating system can be operated in manual mode, independent of a
room controller on a temporary basis. The control system must comply
with Part L1 + L2.
In this case, the CH (boiler) flow temperature setting of the right-hand
dial is used as the temperature for boiler operation. See table 5 “Manual
Operation menu”.
“Service” button
The “Service” button (fig. 4, item 4) is used to display the current
CH (boiler) flow temperature, the current working pressure etc.
Also see section 8.1.1, page 6.
Service Connector
A Worcester service engineer can connect a Service Tool here (fig. 4,
item 5) for diagnostic purposes when servicing.
“Burner” (On/Off) LED
The “Burner” (On/Off) LED (fig. 4, item 6) lights up when the burner
of the boiler is switched on and it is extinguished when the burner is
switched off.
The “Burner” (On/Off) LED indicates the burner status.
“Heat demand” LED
The “Heat demand”LED (fig. 4, item 7) lights up when the control
system has made a heat demand and it is extinguished when this heat
demand is no longer required.
If your heating system consists of several boilers
(cascade system), you have to carry out the settings on
the control units of all individual boilers.
6 720 648 727-010.1TD
6 720 648 727-001.1TD
11 10 9 8 7
65432
1
DANGER: Damage to the installation due to freezing
while manual operation is switched on.
After a power failure or after switching off the supply
voltage, the heating system may freeze since manual
operation is no longer active.
▶ Re-activate manual operation after switching on the
heating system, so that the system is permanently in
operation (especially if there is a risk of freezing).
LED Status Explanation
On Burner
operational
Boiler water is being heated.
Off Burner off The CH (boiler) flow temperature has reached the
set temperature or there is no heat demanded.
Table 3 Meanings of “Burner” (On/Off) LED indications

Operating the heating system
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Maximum CH (boiler) flow temperature dial
The maximum CH (boiler) flow temperature (fig. 4, item 8) is used to
set the upper CH (boiler) flow temperature limit. The unit is °C.
Display
The heating system status and values can be read out from the display
(fig. 4, item 9). If a fault occurs the display will immediately show the
accompanying fault code. The fault code display will flash if a locking
fault is detected.
“DHW mode” LED
The “DHW mode” LED (fig. 4, item 10) lights up when a DHW request
has occurred and it is extinguished when this DHW request is no longer
required.
DHW temperature dial
The DHW temperature dial (fig. 4, item 11) is used to select the
required temperature of the hot water in the hot water cylinder. The unit
is °C. This is only active with certain Bosch controls.
8 Operating the heating system
8.1 Menu structure
You can navigate through the menu structure of the central boiler on the
BC10 using the “Reset” button, the “Chimney sweep” button, the
“Service button” (fig. 6, items 1, 2 and 3) and the display (fig. 6,
item 4) in accordance with the menus in tables 4, 5 and.
Fig. 5 BC10 basic controller
8.1.1 Normal Operation menu
Information about the operating status of the boiler can be displayed via
this menu. The currently measured values of the CH (boiler) flow
temperature (permanent indication), the working pressure and the
operating codes are shown. Proceed as follows:
8.1.2 Manual Operation menu
In manual mode, the heating system can be operated independent of a room controller (e. g. RC35).
DANGER: Damage to the installation with underfloor
heating: by the floor being overheated.
▶ Limit the maximum CH (boiler) flow temperature
using the “CH (boiler) flow temperature” dial
(fig. 4, item 8) to the permissible flow
temperature of the floor heating circuit (usually
maximum 40 °C).
Normal operation menu
Step 1 [\/2/4| Display value. Currently measured
CH (boiler) flow temperature in °C.
Also see section 10.1, page 8.
Step 2 Continue in Normal operation menu? Yes: step 3
No: step 1
Step 3 Press the ebutton.
Step 4 [p/1.6| Display value. Currently measured
system pressure in bar.
Also see section 10.1, page 8.
Step 5 Press the ebutton.
Step 6 [-/h/\| Random display code. In this case:
Operating phase: Boiler in heating
mode. Also see section 10.2,
page 8.
Step 7 Have at least 5 seconds passed without a
button being pressed and/or has the mains
voltage been interrupted ?
Yes: step 1
No: step 8
Step 8 Press the ebutton. step 1
Table 4 Normal operation
6 720 619 373-18.1TD
1 2 3
4
Re-start manual operation after switching on the heating system, so that the system is permanently in operation (especially if there is a
risk of freezing).
Manual operation menu
Step 1 [\/2/4| Display value. Currently measured CH (boiler) flow temperature in °C. Also see section 10.1, page 8.
Step 2 Activate manual operation? Yes: step 3
No: step 1
Step 3 To activate manual operation: Press and hold the dbutton for more than 5 seconds.
Step 4 [\/2/4} Display code: Operating phase: As soon as a flashing dot is shown in the right-hand bottom corner of the
display, manual operation is active. This means that the boiler is permanently in heating mode.
The maximum CH (boiler) flow temperature as set on the maximum CH (boiler) flow temperature dial of
the BC10 basic controller (control panel) now applies. The “Heat request” LED lights up.
Table 5 Manual operation

Extreme Cold Weather
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9 Extreme Cold Weather
In instances where the condensate pipe work is run external or in an
unheated area, such as a garage, it can be at risk of freezing, even if
insulated.
A frozen condensate pipe will cause the boiler to shut down.
If the condensate pipe has frozen:
▶ Locate the blockage.
It is likely that the pipe is frozen at the most exposed point external to
the building or where there is some obstruction to flow. This could be
the open end of the pipe, at a bend or elbow, or where there is a dip
in the pipe in which condensate can collect. The location of the
blockage should be identified as closely as possible before taking
further action.
▶ Thaw the frozen pipe.
The pipe can be thawed by applying a hot water bottle, a
microwaveable heating pack (the sort used for muscular aches and
pains) or a cloth soaked in hot water to the exterior of the pipe, close
to the point of blockage. Hot water can also be poured onto the pipe
from a watering can or similar container.
▶ Once the pipe has been thawed the boiler must be reset, press the
reset button for five seconds and wait two to three minutes for the
boiler to restart.
▶ If the boiler does not restart, contact Worcester’s Technical Support
Team (0330 123 3366) for assistance.
▶ Contact your installer in order to find a permanent solution to the
problem.
Step 5 Press the ebutton.
Step 6 [p/1.6} Display value. Currently measured system pressure in bar. Also see section 10.1, page 8.
Step 7 Press the ebutton.
Step 8 [-/h//} Display code: Operating phase: Also see section 10.2, page 8. The boiler is in manual operation mode.
This means that the boiler is in heating mode while there is no heat request from the controller. During
manual operation the “Settings” menu (table from step 3) can be used to temporarily change the target
boiler performance.
Note: If the boiler performance has been changed temporarily, this must be set again after ending manual
operation, according to the “Settings” menu (table, page).
Step 9 Press the ebutton.
Step 10 [\/2/4} Display value. Currently measured CH (boiler) flow temperature in °C. Also see section 10.1, page 8.
Step 11 Has there been a power failure? Yes: step 1
No: step 12
Step 12 Deactivate manual operation? Yes: step 13
No: step 5
Step 13 To deactivate manual operation:
Press and hold the dbutton for more than 2 seconds until the dot disappears.
step 1
Manual operation menu
Table 5 Manual operation
WARNING: Falling hazard!
Failure to follow this guidance can result in personal
injury.
▶ Only attempt to thaw a condense pipe that is at
ground level, which is easily accessible.
▶ Never attempt to thaw a condense pipe which is at
height.
CAUTION: Pipe damage
▶DO NOT use boiling water to thaw the condensate
pipe!

Display information
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10 Display information
10.1 Display readings 10.2 Display codes
The display shows the operating condition (e. g. a fault)by means of two
three-digit codes.
Refer to section 10.3, “Identifying and resetting faults” on page 9 for
further instructions on how to remedy certain faults.
Please contact your heating engineer if you cannot remedy a fault
yourself or if the display shows a code which is not listed in the table.
Display
reading Key to display reading Unit Range
[\/2/4| Current CH (boiler) flow
temperature. °C [\/\/0|– [1/3/0|
[p/1.6| Current system pressure. bar [\/0.0|– [p/4.0|
Table 6 Display readings
Display code
zMain
display
code zSub
display
code z
e[\/-/\| Operating phase:
Communication test while starting up. This display code flashes five times within 5 seconds while
starting up to indicate that the communication between the UBA 3 and the BC10 basic controller is
being tested. If a new UBA 3 or a new KIM was fitted, this code will flash for max. 10 seconds.
e[-/a/\]
1)
e[2/0/8|
2)
Operating phase:
The boiler is in flue gas test or service mode.
e[-/h/\| e[2/0/0|
2)
Operating phase:
The boiler is in heating mode.
e[-/h/}
3)
e[2/0/0|
2)
Operating phase:
The boiler is in manual operation mode.
e[=/h/\| e[2/0/1|
2)
Operating phase:
The boiler is in heating mode.
e[=/h/\| e[2/0/1|
2)
Operating phase:
Pump run-over time via the external hot water cylinder 130 seconds at the minimum speed.
The “Burner” LED (On/Off) is off.
e[0/a/\| e[2/0/2|
2)
Operating phase:
The switch optimization program is activated. This program is activated if there has been any
demand more frequently than once every 10 minutes. This means that the boiler cannot be
restarted until at least 10 minutes have elapsed since initial burner start-up.
e[0/a/\| e[3/0/5|
2)
Operating phase:
The boiler cannot start up temporarily after a DHW request has ended.
e[0/c/\| e[2/8/3|
2)
Pre-operative phase:
The boiler prepares for a burner start-up whenever a heat demand or a DHW request arises.
e[0/e/\| e[2/6/5|
2)
Readiness for operation:
The boiler is in ready mode. There is a current heat demand, but too much energy has been supplied.
e[0/h/\| e[2/0/3|
2)
Readiness for operation:
The boiler is in ready mode. There is no current heat demand.
e[0/l/\| e[2/8/4|
2)
Ignition phase:
The gas valve is activated.
e[0/u/\| e[2/7/0|
2)
Start-up phase:
The boiler starts up after activation of the mains power supply or completion of a system reset.
This code is displayed for a maximum of 4 minutes.
e[0/y/\| e[2/0/4|
2)
Operating phase:
The flow temperature sensor has detected that the current flow temperature is higher than the flow
temperature setting on the BC10, or that it is higher than the flow temperature. Calculated
according to heating requirements, or that it is higher than the flow temperature calculated for the
DHW mode.
e[2/e/\| e[2/0/7|
2)
eFault:
The system pressure is too low (less than 0.2 bar).
[8/8/8| Function test:
Display test during start-up phase. The display code is displayed for a maximum of 1 second.
Table 7 Display codes

Display information
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10.2.1 Fault or Breakdown
This boiler is supported in the UK and Eire by Worcester, Bosch Group.
Specialist Service Engineers are available to attend a breakdown
occurring on this boiler.
• No charge will be made for parts and/or labour providing:
A boiler fault is found and the appliance has been installed within the
past 24 months. Reasonable evidence of this must be supplied on
request. i.e. the Benchmark Checklist.
• A call-out charge will be made where:
– The boiler has been installed for over 24 months.
– Evidence cannot be provided that the first year service inspection
has been carried out (i.e. an entry in the Benchmark Checklist).
– Our Field Service Engineer finds no fault with the boiler.
– The cause of breakdown is misuse or with other parts of your
plumbing/heating system, or with equipment not supplied by
Worcester, Bosch Group.
Technical Support
In the event of a boiler fault or breakdown please contact Worcester,
Bosch Group appointments team on 0033 123 9339.
Your advisor will arrange for an engineer to call with the minimum of
delay; under normal circumstances this will be from 1 - 3 working days
(excluding weekends) for priority breakdown situations (no hot water
and/or heating).
10.3 Identifying and resetting faults
Fault messages can be identified by the flashing display:
▶ Press the “Reset” button (fig. 6, item 1) for approx. 5 seconds to
reset the fault.
Fig. 6 BC10 – “Reset” button
The display shows [\/r/e|. The boiler tries to reset the fault. If the display
shows a normal operating code afterwards, the fault has been remedied.
Otherwise, please repeat the reset two or three more times.
If the fault cannot be reset
If the fault remains and cannot be cleared by pressing the reset button,
contact Worcester, Bosch Group for assistance.
e[a/1/1| e[8/0/2|
2)
eFault:
Time not set. Failing time setting, e.g. due to a long power cut.
e[a/1/1| e[8/0/3|
2)
eFault:
Date not set. Failing date setting, e.g. due to a long power cut.
[h/\/7| Operating phase:
The system pressure is too low (less than 1.0 bar).
e[h/\/7| eOperating phase:
The system pressure is too low (less than 1.0 bar).
[p/-.-| Operating phase:
The system pressure is too high (over 4.0 bar) or the pressure sensor has not detected a system
pressure (boiler functioning normally).
[\/r/e| Fault:
Reset is carried out. After pressing the “Reset” button this code is displayed for 5 seconds.
1) Any indication with a permanent dot in the bottom right-hand corner
2) Only visible on the Service Tool or a specific RC regulator.
3) Any indication with a flashing dot in the bottom right-hand corner.
Display code
zMain
display
code zSub
display
code z
Table 7 Display codes
Invoices for attendance and repair work carried out on
this boiler by any third party will not be accepted.
No boiler fault is found on over 30% of all service calls.
In the case of a suspected fault, refer to the fault finding
section of this guide.
CAUTION: Damage to the installation.
In frost conditions, the heating system may freeze up if it
is not operational, e. g. due to a power failure.
▶ If the heating system is switched off for a couple of
days due to a fault and there is a risk of frost, the
heating water must be drained at the lowest point of
the system to prevent it from freezing.
6 720 619 373-22.1TD
1

Tips on energy saving
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11 Tips on energy saving
HEATING ECONOMICALLY
The boiler provides a high level of comfort whilst keeping gas
consumption and the environment effects as low as possible.
The gas supply to the burner is controlled according to the level of
demand for heat. The boiler operates with a low flame if the demand for
heat reduces. The technical term for this process is modulating control.
Modulating control reduces temperature fluctuations and provides an
even distribution of heat throughout the home. This means that the
boiler may stay on for relatively long periods of time but will use less gas
than a boiler that continually switches on and off.
CENTRAL HEATING SYSTEMS WITH ROOM THERMOSTAT/
THERMOSTATIC RADIATOR VALVES
With modern heating systems set around a 20 °C heat loss, the optimum
setting for a condensing boiler will be approximately between one and
two on the central heating temperature control. The system must be
balanced correctly and the radiators may need upgrading. This allows
the boiler to condense as much as possible for the central heating
system.
The temperature of each room can be set individually (except primary
room with the room thermostat) using the thermostatic radiator valves.
ROOM THERMOSTATS
Reducing the setting of the room thermostat by 1 °C can reduce fuel
consumption by up to 10%.
NEW CONTROL SYSTEMS
Upgrade your heating control system if necessary with the latest
equipment available. The minimum level of control is a programmer,
interlocking room thermostat and thermostatic radiator valves.
ROOF INSULATION
Around 30% of the heat loss from a property is through the roof. Replace
any old insulation with new insulation, preferably of around 200 mm
thickness or more.
WINDOW FRAMES
Single glazed windows, particularly those with steel frames, can lose a
great deal of heat. Consideration should be given to replacement with
PVCu or wooden framed double glazed units.
RADIATORs
If a radiator is sited underneath a window, its performance will be
affected if the curtains are allowed to drape over the radiator. Shelves
fitted above or in front of the radiator should also be avoided.
It is advisable to manually adjust all thermostatic radiator valves every 2
- 3 months to prevent them sticking. Ensure radiator valves are correctly
set and not damaged.
DRAUGHTS
Try to ensure that draughts around doors, windows, letterboxes and
keyholes etc. are
reduced by using a suitable draught excluder.
CURTAINS
Lined curtains, or heavier full length curtains can provide excellent
insulation. However, always ensure that the curtains do not drape over
radiators.
12 Environment / disposal
Environmental protection is a fundamental corporate strategy of the
Bosch Group.
The quality of our products, their economy and environmental safety are
all of equal importance to us and all environmental protection legislation
and regulations are strictly observed.
We use the best possible technology and materials for protecting the
environment taking account of economic considerations.
Packaging
We participate in the recycling programmes of the countries in which our
products are sold to ensure optimum recycling.
All of our packaging materials are environmentally compatible and can
be recycled.
WARNING: AIR VENTS
▶ Do not block or seal any air vents that are installed to
ensure that the central heating boiler operates
safely.

Your Guarantee
6720813172 (2015/04) 11
13 Your Guarantee
This boiler is guaranteed against faulty materials or workmanship for a
period of 2 years from the date of installation subject to the following
terms and conditions.
• During the period of this guarantee any components of the boiler
which are proven to be faulty or defective in manufacture will be
exchanged or repaired free of charge by Bosch Thermotechnology
Ltd..
• The householder may be asked to prove the date of installation, that
the boiler was correctly commissioned and, where appropriate, the
first year‘s service has been carried out to the satisfaction of Bosch
Thermotechnology Ltd. when requested. These should be part of the
Installation Checklist.
• The boiler has been used only for the purposes for which it was
designed.
This guarantee does not affect your statutory rights.
GUARANTEE REGISTRATION
Returning the card will register you as the owner of your new gas boiler
and will assist us in maintaining an effective and efficient customer
service by establishing a reference and permanent record for your
boiler.
For your own record:
Please ensure that the Installation Checklist has been completed by your
installer or service engineer.
Model
Serial No.1)
1) See identity label on the top of the appliance.
Type/size
Date of installation
Name of Installer
Telephone number of Installer
Table 8

Worcester, Bosch Group
Cotswold Way, Warndon, Worcester WR4 9SW.
Tel. [phone]
Worcester, Bosch Group is a brand name of Bosch Thermotechnology Ltd.
worcester-bosch.co.uk
6720813172
WORCESTER, BOSCH GROUP:
TECHNICAL SUPPORT: 0330 123 3366
APPOINTMENTS: 0330 123 9339
SPARES: 0330 123 9779
LITERATURE: 0330 123 9119
TRAINING: 0330 123 0166
SALES: 0330 123 9669