British Gas ICC2 combi ZWBR 8-30 ICC2 Installation And Servicing Instructions

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Page 1

Installation and Servicing Instructions

ICC2 combi

Wall mounted condensing boiler for central heating and mains fed domestic hot water

6 720 610 598-00.1

ZWBR 8-30 ICC2

GC-Number: 41 108 09

ZWBR 11-37 ICC2

GC-Number: 41 108 10

6 720 610 602 GB (03.02) OSW

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6 720 610 602 GB (03.02)

Contents

Safety precautions 3

Symbols 3

1 Details of the appliance 4

1.1 EC Declaration of Conformity 4

1.2 Standard package 4

1.3 Description of appliance 4

1.4 Accessories 5

1.5 Casing dimensions 5

1.6 Layout of appliance 6

1.7 Function 7

1.8 Electrical wiring diagram 8

1.9 Technical data 9

2 Installation regulations 10

3 Installation 11

3.1 Important remarks 11

3.2 Domestic hot water 11

3.3 Sealed systems 11

3.4 Siting the appliance 12

3.5 Wall mounting frame assembly 13

3.6 Pre-piping the system 13

3.7 Fitting the appliance 14

3.8 Checking the connections 15

3.9 Flue Systems 15

3.9.1 Siting the Flue Terminal 16

3.9.2 Installation of the flue 17

3.9.3 Flue duct preparation and assembly 19

4 Electrical connections 20

4.1 Connecting the appliance 20

4.2 Connecting TR2 Room thermostat 21

4.3 Mains Voltage external controls connections 21

5 Commissioning 22

5.1 Commissioning 22

5.2 Switching the appliance on/off 23

5.3 Switching on the central heating 23

5.4 System controls 23

5.5 Setting the domestic hot water temperature and flow rate 24

5.5.1 Domestic hot water temperature 24

5.5.2 Hot water flow rate 24

5.6 Summer mode (hot water only) 24

5.7 Frost protection 24

5.8 Pump anti-seize function 24

5.9 Fault Condition 25

6 Text Display 26

6.1 General Description 26

6.2 Programming 26

6.2.1 Deleting a setting 27

6.2.2 Resetting all parameters to their original settings 27

6.3 Menu structure 27

6.4 Setting the time/day 28

6.4.1 Setting the time and day 28

6.4.2 Holidays 28

6.5 Heating 28

6.5.1 Heating programme 28

6.5.2 Setting the Economy temperature (if TR2 is connected) 28

6.5.3 Manual operating mode (if TR2 is not connected) 29

6.6 Hot water 29

6.6.1 Hot water programme 29

6.6.2 Hot water immediately 29

6.7 i Info 29

6.8 Settings 30

6.8.1 Heating (if TR 2 is connected) 30

6.8.2 Hot Water (Storage Tank, ZSBR models only) 30

6.8.3 Service 30

6.9 Individual timer programmes 30

7 Individual settings 31

7.1 Mechanical settings 31

7.1.1 Checking the size of the expansion vessel 31

7.1.2 Setting the central heating flow temperature 31

7.2 Settings on the Bosch Heatronic 31

7.2.1 General description 31

7.2.2 Setting the anti-cycle time (Service Function 2.4) 32

7.2.3 Setting the maximum CH flow temperature (Service Function 2.5) 32

7.2.4 Setting the heating output (Service Function 5.0) 32

7.2.5 Constant hot water cycle time (Service Function 6.8) 32

7.2.6 Variable pump settings (Service Function 7.0) 32

7.3 Setting the gas/air ratio 32

8 Converting the appliance to different

gas types 33

8.1 Setting the gas/air ratio 33

8.2 Testing combustion air/flue gas at set heat output 35

8.2.1 Testing the O2 or CO2 level in the combustion air 35

8.2.2 Testing CO and CO2 35

9 Maintenance 36

9.1 Pre-Service Check List 37

9.2 Description of servicing operations 38

9.3 Replacement of Parts 41

9.3.1 PCB control board and transformer 41

9.3.2 Fan Assembly 42

9.3.3 Pump 42

9.3.4 3-way diverter valve 43

9.3.5 3-way diverter valve motor 43

9.3.6 Sensors 43

9.3.7 Gas Valve 44

9.3.8 Domestic Hot Water Heat Exchanger 44

9.3.9 Electrode assembly 44

9.3.10Pressure gauge 44

9.3.11Expansion vessel 44

9.3.12Pressure Relief Valve 44

9.3.13Burner 44

9.3.14Flow switch 45

9.3.15Primary Heat Exchanger 45

10 Appendix 46

10.1 Fault Codes 46

10.2 Short parts list 47

10.3 Heating/hot water output settings ZWBR 8-30 N.G. 48

10.4 Heating/hot water output settings ZWBR 11-30 L.P.G 48

10.5 Heating/hot water output settings ZWBR 11-37 N.G. 48

10.6 Heating/hot water output settings ZWBR 14-37 L.P.G 48

10.7 Operational Flow diagrams 49

10.7.1Domestic hot water function 49

10.7.2Central heating function 50

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Safety precautions

If you smell gas

Turn off gas service cock at the meter.

Open windows and doors.

Do not operate any electrical switches.

Extinguish any naked flames.

Telephone your gas company.

If you smell fumes from the appliance

Switch off appliance (see page 23).

Open windows and doors.

Fitting and modifications

Fitting of the appliance or any controls to the appliance may only be carried out by a competent engineer in accordance wth the Gas Safety (Installation and Use) Regulations 1998.

Flue systems must not be modified in any ways other than as described in the fitting instructions.

This appliance is for use on sealed primary systems only.

Maintenance

The user is recommended:

to have the system regularly serviced in order to ensure that it functions reliably and safely.

Use only original spare parts!

Combustible materials

Do not store or use any combustible materials (paper, thinners, paints etc.) in the vicinity of the appliance.

Health and safety

This appliance contains no asbestos products.

There is no potential hazard due to the appliance being electrically unsafe.

There are no substances used in the construction that are a potential hazard in relation to the COSHH Regulations (Control of Substances Hazardous to Health Regulations 1988).

Combustion air/Ambient atmosphere

The combustion air/ambient atmosphere should be kept free of chemically aggressive substances (e.g. halogenated hydrocarbons which contain chlorine or fluorine compounds). This will prevent corrosion.

Instructions to the customer

Explain to the customer how the appliance works and how to operate it.

Advise the user that he/she must not make any modifications to the appliance or carry out any repairs on it.

These instructions are to be left with the user or at the Gas meter.

Important: These instructions apply in the UK only.

Symbols

Safety instructions

in this document are identified by a warning-triangle symbol and are printed on a grey background.

Notes

containing important information are identified by the symbol shown on the left. They are bordered by horizontal lines above and below the text.

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Details of the appliance

1 Details of the appliance

1.1 EC Declaration of Conformity

This appliance is in accordance with the applicable requirements of the Gas Appliance Directive, Boiler Efficiency Directive, Electromagnetic Compatibility Directive and the Low Voltage Directive.

1.2 Standard package

•

Gas condensing combination boiler for central heating and domestic hot water

•

Control panel cover

•

Wall mounting frame

•

Room thermostat TR2

•

Clamp for securing flue duct kit

•

Fixings (screws etc.)

•

Set of documentation for appliance

•

Pre-plumbing manifold

•

Condensate drain pipe

•

Filling loop.

1.3 Description of appliance

•

Wall-mounted appliance, siting not dependent on room size

•

Natural gas models are low-emission appliances

•

Multifunction display

•

Bosch Heatronic control system with integrated textdisplay for servicefunctions and faults

•

3-channel - digital timer for one heating circuit

•

Variable pump

•

Automatic ignition

•

Modulating control

•

Full safety systems incorporating Bosch Heatronic with flame ionisation monitoring, solenoid valves and temperature sensors

•

Concentric flue/air duct with testing point for CO2/CO

•

Regulated speed fan

•

Pre-mix burner

•

Temperature control for central heating

•

Temperature sensor in domestic hot water

•

Safety temperature limiter in 24 V electrical circuit

•

Relief valve, pressure gauge, expansion vessel

•

Flue gas temperature limiter (105 °C)

•

Hot water priority circuit

•

Motorised 3-way valve

•

Plate-type heat exchange

•

Condensate Trap.

CE-0085 BL0507

Category UK

2H 3P

Appliance Type

C13, C

Table 1

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Details of the appliance

1.4 Accessories

•

Standard horizontal flue kit at 100 mm outside diameter for flues upto 4 m in length.

•

Flue duct kits for horizontal (125 mm outside diameter) for flue lengths upto 10 m (ZWBR 11-37) or 13 m (ZWBR 8-30) and vertical flue systems for flue lengths 12 m (ZWBR 11-37) or 15m (ZWBR 8-

30). Fitting instructions are sent with these kits.

•

Heating programmer,

•

Security kit.

1.5 Casing dimensions

Fig. 1

Manifold assembly

101

Outer case

103

Facia cover

Standard Concentric Horizontal Flue System: min. 310 mm Alternative Concentric Flue System: min. 250 mm

Standard Concentric Horizontal Flue System: 158 mm Alternative Concentric Flue System: 121 mm

Standard Concentric Horizontal Flue System: 105 mm Alternative Concentric Flue System: 130 mm

For servicing the appliance

min.

512

850

101

103

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200

395

360

861

906

120

200

600

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Details of the appliance

1.6 Layout of appliance

Fig. 2

4 Heatronic control 6 Heat exchanger safety temperature limiter

6.1 Hot water NTC sensor 7 Testing point for gas supply pressure

8.1 Pressure gauge 9 Flue gas temperature limiter 15 Relief valve 18 Pump 20 Expansion vessel 27 Automatic air vent 29 Air gas Mixer unit

32.1 Electrode assembly 36 Temperature sensor in CH flow 43 CH flow 63 Adjustable gas flow restrictor 64 Adjusting screw for min. gas flow volume 88 3-way valve (combi) 98 DHW flow switch (combi) 102 Inspection window

120 Fixing points

221.1 Flue duct

221.2 Combustion air intake 226 Fan assembly 295 Appliance type sticker 234 Testing point for combustion products

234.1 Testing point for combustion air 271 Flue duct 349 Cover plate for twin flue duct connection 355 Plate-type domestic hot water heat exchanger 358 Condensate trap 396 Hose Condensate trap 400 Textdisplay 415 Cover plate for cleaning access 416 Condensate collector 418 Data plate 423 Siphon

102

226

234.1

271

416

221.1

221.2

358

355

6.1

415

32.1

234

349

295

8.1

120

418

400

396

423

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Details of the appliance

1.7 Function

Fig. 3

4 Bosch Heatronic control 6 Temperature limiter, heat exchanger

6.1 Hot water NTC sensor 7 Testing point for gas supply pressure

8.1 Pressure gauge 9 Flue gas temperature limiter 13 Manifold 15 Safety valve 18 Central heating pump 20 Expansion vessel 26 Charging valve 27 Automatic vent 29 Mixer unit

29.1 Bi-metallic thermostat for combustion air compensation 30 Burner 32 Flame sensing electrode 33 Igniter electrode 35 Heat exchanger with cooled combustion chamber 36 Temperature sensor in CH flow 43 CH flow 44 Hot water flow 45 Gas 46 Cold water inlet 47 CH return 52 Solenoid valve 1

52.1 Solenoid valve 2 55 Filter 56 Gas valve CE 427 57 Main valve disc 61 Reset button 63 Adjustable gas flow restrictor

64 Adjusting screw for min. gas flow volume 69 Control valve 84 Motor 88 3-way valve 90 Venturi 91 Pressure relief valve 93 Water flow regulator 94 Diaphragm 95 Pushrod with switch cam 96 Microswitch 97 Valve for hot water flow volume 98 Water valve 221 Flue duct 226 Fan 229 Air box 234 Testing point for flue gas

234.1 Testing point for combustion air 317 Display 355 Plate-type heat exchanger 358 Condensate trap 400 Textdisplay 423 Siphon 443 Diaphragm

332930

226

229

234

234.1

29.1

45 47

8.1

52.1

355

358

max

ECO

317

400

221

6.1

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Details of the appliance

1.8 Electrical wiring diagram

Fig. 4

4.1 Ignition transformer 6 Temperature limiter, heat exchanger

6.1 Hot water NTC sensor 9 Flue gas temperature limiter 18 Pump 32 Flame sensing electrode 33 Ignition electrode 36 Temperature sensor in CH flow 52 Solenoid valve 1

52.1 Solenoid valve 2 56 Gas valve CE 427 61 Reset button 84 Motor, 3-way valve 96 Microswitch, hydraulic switch 135 Master switch 136 Temperature control for CH flow 151 Fuse, slow 2.5 A, AC 230 V 153 Transformer 161 Link 226 Fan 300 Code plug 302 Earth connection 310 Temperature control for hot water 312 Fuse, slow T 1,6 A 313 Fuse, slow T 0,5 A 317 Digital display 328 Terminal block for AC 230 V Mains supply

328.1 Link 363 Indicator lamp for burner 364 Indicator lamp for power supply

365 “Chimney sweep” button 366 Service button 367 ECO button 400 Textdisplay 422 Connecting TR2

52.1

230 V

135

25 V

230V/AC

153

136

151

1247

161

226

300

NLsNs

328

302

310

312

313

317

363

364

365

366

ECO

367

4.1

328.1

6.1

400

43F

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mains supply

422

o - orange g - green bl - black r - red p - purple

r r

bl bl bl

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Details of the appliance

1.9 Technical data

Units

ZWBR 8-30

Natural gas

ZWBR 11-30

Propane

ZWBR 11-37

Natural gas

ZWBR 14-37

Propane

Max. rated heat output net 40/30˚C central heating Max. rated heat output net 50/30˚C central heating Max. rated heat output net 80/60˚C central heating

kW kW kW

32.3

31.9

30.2

32.3

31.9

30.2

39.7

39.2

37.1

39.7

39.2

37.1 Max. rated heat input net kW 30.5 30.5 37.5 37.5 Min. rated heat output net 40/30˚C Min. rated heat output net 50/30˚C Min. rated heat output net 80/60˚C

kW kW kW

9.5

9.4

8.2

12.7

12.6

11.0

12.9

12.8

11.4

16.2

16.1

14.3 Min. rated heat input net kW 8.8 11.8 11.8 14.8 Max. rated heat output net, domestic hot water kW 30.2 30.2 37.1 37.1 Max. rated heat input net, domestic hot water kW 30.5 30.5 37.5 37.5 Maximum gas flow rate – After 10 minutes from lighting

Natural gas G20 (CVnet 34.02 MJ/m

)

m3/h

3.2 3.9

LPG (CVnet 88 MJ/m

)

kg/h 2.2 2.7

Gas supply pressure

Natural gas G20 (CVnet 34.02 MJ/m

)

mbar 20 - 20 -

LPG (CVnet 88 MJ/m

)

mbar - 37 - 37

Expansion vessel

Charge pressure bar 0.75 0.75 0.75 0.75 Total capacity l 10 10 10 10 Hot water specifications Hot water flow rate (factory setting) l/min 8 8 8 8 Max. hot water flow rate l/min 14.0 14.0 14.0 14.0 Outlet temperature range ˚C 40 - 60 40 - 60 40 - 60 40 - 60 Max. permissible water supply pressure bar 10 10 10 10 Min. inlet pressure bar 0.2 0.2 0.2 0.2 Specific flow rate l/min 13.7 13.7 16.9 16.9 Flue Flue gas temp. 80/60˚C, rated/min. load ˚C 78/57 78/57 87/58 87/58 Flue gas temp. 40/30˚C, rated/min. load ˚C 58/35 58/35 65/43 65/43 Residual delivery pressure (inc. pressure drop in air intake duct)

Pa 90 90 100 100

CO2 level at max. rated heat output CO2 level at min. rated heat output

% %

9.4

9.2

11.0

9.2

11.0

11.0 NOx-class 5 5 5 5

SEDBUK figure, Band A % 90.3 90.3 90.3 90.3

Condensate

Max. condensation rate (tR = 30˚C) l/h 2.6 2.6 3.2 3.2 pH-value, approx. 4.8 4.8 4.8 4.8

General Data

Electrical power supply voltage AC ... V 230 230 230 230 Frequency Hz 50 50 50 50 Max. power consumption W 156 156 161 161 Noise output level dB(A) 39 39 41 41 Appliance protection rating IP X4D X4D X4D X4D Max. CH flow temperature ˚C nom. 90 nom. 90 nom. 90 nom. 90 Max. permissible operating pressure (CH) bar 2.5 2.5 2.5 2.5 Permissible ambient temperatures ˚C 0 - 50 0 - 50 0 - 50 0 - 50 Nominal capacity of appliance l 3.75 3.75 3.75 3.75 Weight kg 53 53 53 53

Table 2

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Installation regulations

Condensate analysis, mg/l

Flue system

Elbow - 90 ° Equivalent length 2 m Bend - 45 ° Equivalent length 1m

Gas supply

Domestic water performance

2 Installation regulations

Gas Safety (Installation & Use) Regulations 1998: All gas appliances must be installed by a competent person. Failure to install correctly could lead to prosecution. The manufacturers notes must not be taken, in any way, as overriding statutory obligations. The appliance must be installed in accordance with the current IEE Wiring Regulations, local Building Regulations, Building Standards (Scotland) (Consolidation), bye-laws of the local Water Company, Health and Safety Document 635 (Electricity at Work Regulations

1989) and any other local requirements. Product Liability regulations indicate that, in certain circumstances, the installer can be held responsible, not only for mistakes on his part but also for damage resulting from the use of faulty materials. We advise the installer to avoid any risk by using only quality approved branded fittings. The relevant British Standards should be followed i.e.

• BS 6798: Specification for the installation of gas

fired hot water boilers of rated input not exceeding 60kW

• BS 5449: Central Heating for Domestic Premises

• BS 5546: Installation of gas hot water supplies for

domestic purposes

• BS 5440:1: Flues and ventilation for gas appliances

of rated input not exceeding 70 kW (net): Flues

• BS 5440:2: Flues and ventilation for gas appliances

of rated input not exceeding 70 kW (net): Air Supply

• BS 6891: Installation of low pressure gas pipework

installations up to 28mm (R1).

• BS 7074:1: Code of practice for domestic heating

and hot water supply

• BS 7671: Requirements for Electrical Installation. These instructions must be followed.

Ammonium 1.2 Nickel 0.15 Lead ≤ 0.01 Mercury ≤ 0.0001 Cadmium ≤ 0.001 Sulphate 1 Chromium ≤ 0.005 Zinc ≤ 0.015

Halogenated hydrocarbons ≤ 0.002

Tin ≤ 0.01

Hydrocarbons 0.015 Vanadium ≤ 0.001

Copper 0.028 pH-value 4.8

Table 3

HORIZONTAL 100 mm – Standard

Overall Diameter of Duct mm 100

Max. 4 m

Flue Terminal / Duct Assembly Length

mm 600

Extension Duct Length mm 1000

Table 4

ALTERNATIVE HORIZONTAL 125 mm FLUE SYSTEM

Overall Diameter of Duct mm 125 Max. 13 m

(ZWBR 8-30)

Max. 10 m (ZWBR 11-37)

including turret

Flue Terminal / Duct Assembly

mm 1030

Table 5

VERTICAL 125 mm FLUE SYSTEM

Overall Diameter of Duct mm 125 Max. 15 m

(ZWBR 8-30)

Max. 12 m (ZWBR 11-37)

Flue Terminal / Duct Assembly

mm 1360

Table 6

Total length of gas supply pipe (metres)

Pipe diameter (mm)

369

Gas discharge rate (m

/h)

8.7 5.8 4.6 22

18.0 12.0 9.4 28

Table 7

ZWBR 8-30

ZWBR 11-37

Domestic Water Flow Rate l/min

Temperature Rise

30 °C 14.6 18.0

Temperature Rise

35 °C 12.5 15.4

Temperature Rise

40 °C 11.0 13.5

Maximum Mains pressure bar 10.0 10.0

Minimum Mains pressure bar 0.2 0.2

Table 8

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Installation

3 Installation

3.1 Important remarks

B Appliance should only be installed in sealed central

heating and hot water systems.

B To avoid gas formation in the system, galvanised

radiators or pipes must not be used.

B If a room thermostat is used: do not fit a thermostatic

radiator valve on the radiator in the primary room.

B This appliance uses an automatically variable pump.

An auto-bypass must not be fitted.

B Add a suitable anti-freeze fluid to the water in the

central heating system. Suitable products are available from Betz-Dearborn Tel.: 0151 4209563 and Fernox Tel.: 01799

550811.

B In our experience, the addition of sealing agents to

the water in the central heating system can cause problems (deposits in the heat exchanger). For that reason we advise against their use.

3.2 Domestic hot water

Any regulations specified by the local water company must be observed.

The final 600 mm of the mains cold water connection to the applaince should be made in copper tube only.

The appliance is suitable for a mains supply having a maximum pressure of 10 bar. A pressure reducing valve must be fitted, if necessary.

The hot water outlet temperature is set to be capable of achieving a maximum of 60˚C. The maximum temperature and the frequency of the recharge of the heat store may be reset.

The water flow rate of 11.0 l/min (ZWBR 8-30) and

13.5 l/min (ZWBR 11-37) will give a temperature rise of 40˚C. If a higher rise is required then the flow must be reduced at the tap and the discharge temperature will rise up to the maximum set figure.

The temperature rise, upto the maximum set by the user, is automatically maintained by the modulation of the heat input. In winter, when the mains temperature is very low, the water flow, adjusted at the tap or shower, should be reduced to maintain the required delivery temperature.

It is suggested that long pipe runs to taps or showers be insulated to prevent the rapid cooling of the water.

All types of single lever mixer taps and thermostatic mixer units suitable for a mains pressure of up to 10 bar can be used.

The head of a loose-head shower must not be allowed to fall within 25 mm of the top the bath to prevent the risk of water being drawn back into the mains. Alternatively the shower must be fitted with an anti-syphonage device at the point of the flexible hose connections.

Over-rim bidets may be connected to the appliance provided that it is in accordance with the requirements of the local water company. The outlet(s) should be shrouded and unable to have any temporary hand held spray attached. No anti-syphonage arrangements are necessary.

In exceptionally hard water areas a device to prevent scale formation may be fitted or, alternatively, the maximum temperature reset to about 45˚C which may reduce the risk of scale formation. The installation of a scale inhibitor assembly should be in accordance with the requirements of the local water company. Artificially softened water must not be used to fill the central heating system. An isolating valve should be fitted to allow for servicing.

Devices, such as water meters or back-flow prevention valves, capable of preventing the flow of expansion water must not be fitted unless separate arrangements have been made.

A Zilmet Z160 expansion vessel is the preferred type. A thread sealant compatible with potable water must be used. The vessel should be connected into the cold water mains inlet pipe as close as possible to the appliance.

3.3 Sealed systems

The appliance must not be operated without the system being full of water, properly vented and pressurised.

The expansion vessel has a volume of 10 litres and is charged to a pressure of 0.75 bar.

The water capacity of the system is shown in table 11, page 31. If a greater capacity is required then an additional expansion vessel must be fitted into the system return as close to the appliance as possible. The system pressure can be set up to a maximum of 1.5 bar with 1 bar being the normal setting.

If the system pressure is greater than 2.5 bar when the appliance is operating at maximum temperature then an additional expansion vessel must be fitted into the system return as close to the appliance as possible.

The filling point must be at low level and arranged as shown in figs. 5 and 6.

The pressure relief valve is set to operate at 3 bar. There must be no connection to the mains without the

approval of the local water company. All connections in the system must be capable of withstanding a pressure

B Always turn off the gas cock before car-

rying out any work on components which carry gas.

Fixing of the appliance, gas and flue connections, commissioning of the system and electrical connections may only be carried out by competent persons authorised by CORGI.

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6 720 610 602 GB (03.02)

Installation

of up to 3 bar and the radiator valves conform to the requirements of BS2767:10.

If Thermostatic Radiator Valves are fitted then it is recommended that the primary radiator is left open.

Repeated venting probably indicates a leak and this must be rectified to ensure the proper operation of the appliance.

No galvanised radiators or pipes must be used. If any system water treatment is required then

only products suitable for use with Aluminium shall be used i.e Fernox- Copal or Superconcentrate or Sentinal X100, in accordance with the

manufacturers instructions. The use of any other substances will invalidate the guarantee. The pH value of the system water must be less than 8 or the appliance guarantee will be invalidated.

A drain cock to BS2879 must be fitted to the lowest point of the system.

IMPORTANT: Check that no dirt is left in the water pipework as this could damage the appliance. Thoroughly flush the heating system and the mains water supply before fitting the appliance to the wall in accordance with the recommendations of BS7593:1992.

Fig. 5 Sealed primary water system

Fig. 6

3.4 Siting the appliance

Regulations concerning the Installation Site

B Relevant national regulations must be complied with

section 3.9.1.

B Consult the installation instructions for details of min-

imum clearances required.

Combustion air

In order to prevent corrosion, the combustion air must not contain any corrosive substances.

Substances classed as corrosion-promoting include halogenated hydrocarbons which contain chlorine and fluorine compounds and are contained in some solvents, paints, adhesives, aerosol propellants and household cleaners, for example.

Surface temperature

The max. surface temperature of the casing and the flue is less than 85 °C. This means that, no special safety precautions are required with regard to flammable building materials and fitted furniture. The specified clearences must be maintained.

Domestic hot water

Central heating flow

Radiator

valve

Lockshield

valve

Central heating return

A drain cock should be fitted at the lowest point of the heating circuit and the appliance

Water main

BS stop valve. Fixed spindle type

APPLIANCE

Refer to Fig.1

Appliance water flow

diagram

WRAS approved

filling loop

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Heating return

Non return

valve

Non return

valve

Hose union

Test cock

Temporary hose

Stop cock

Auto

air vent

Heating return

Stop cock

Fill point

Non return valve

Make up

vessel

1000mm (39 in) above the highest point of the system.

Sealed system filling and make up

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Installation

Cupboard/Compartment

The appliance can be installed in a cupboard/compartment need for airing clothes providing that the requirements of BS6798 and BS5440:2 are followed. The low casing losses from the appliance eliminate the need for ventilation openings in the compartment.

3.5 Wall mounting frame assembly

B Take the wall mounting frame out of the package and

screw together with 6 screws as shown in fig. 7. Use the outer lugs on the top and bottom horizontal sections for the appliances that are 512 mm wide.

Fig. 7

B Hold the wall-mounting frame against the wall ensur-

ing that it is vertical.

B Mark the position of the flue duct hole if a rear flue is

to be used. Refer to fig. 1 and 16.

B Mark the holes for the wall mounting frame onto the

wall, drill and plug the holes and screw the wall mounting frame to the wall with the screws provided.

Fig. 8

B Screw the pre-plumbing manifold with two screws to

the wall mounting frame.

Fig. 9

3.6 Pre-piping the system

Fig. 10 Manifold

43 CH flow 47 CH return 112 Gas cock 171 Domestic hot water 172 Cold water relief

B A drain tap should be fitted at the lowest point of the

central heating system.

B WRAS approved filling loop must be fitted.

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200

260

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120-130

4743

172112

171

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Installation

Condensate Termination and Route

The condensate connection on the British Gas/Bosch appliances is in 22 mm plastic. The pipe should be extended and run away from the appliance with a constant fall of 2.5 ° or 40 mm in every metre.

The condensate pipe can terminate into any of four areas:

Fig. 11

Whilst all of the above methods are acceptable it is always the best practice to terminate the condense pipe via an internal waste system.This will eliminate the need for any external condensate pipe runs which can be susceptible to freezing in extreme weather.

Fig. 12 Position of the condensate drain

External condensate pipework

All British Gas/Bosch condensing boilers have within a syphonic condensate trap. Rather than the condensate constantly dripping into the discharge pipe, the condensate is collected into a trap which releases it in 100 ml quantities. This will help prevent freezing occurring.

If there is no alternative and the condensate pipe has to be externally run, the following should be considered:

• The pipe run should take the shortest practical route.

• The pipework should be insulated with weather

resistant insulation.

• The pipe should terminate as close as possible to the

ground or drain, whilst still allowing the condensate to safely disperse. This would prevent wind blowing up the pipe.

• The pipework should be installed with the minimum

of horizontal runs and with a downward slope of at least 2.5 °.

3.7 Fitting the appliance

B Remove packing, taking care to observe the instruc-

tions on the packing.

B Lie the boiler on its back.

Removing the outer case

B Remove retaining screw on left hand side (1). B Press both catch levers backwards (2).

Boiler

Sink

Ø 22 min.

Siphon

75 min. trap

Invert

No length restriction

Internal soil and vent stack

The gradient of the discharge pipe should be 2.5° (40 mm/m) minimum

An internal waste system

An external waste system

The rainwater system

An external purpose made soakaway

The gradient of the discharge pipe should be

2.5° (40 mm/m) minimum

Use waterproof pipe work insulation in very exposed positions

External length of pipe 2m min.

Open end of pipe direct into gully, below ground but above water level.

Open end of pipe direct into gully, below ground but above water level

75 min. trap

450 min.

Siphon

75 min. trap

Boiler

6 720 610 596 -03.1O

Boiler

Sink

6 720 610 602 - 03.1O

Benchmark: For optimum performance after installation, this boiler and its associated central heating system must be flushed in accordance with the guidelines given in BS5793:1992 “Treatment of water in domestic hot water central heating systems”.

The outer case is secured against unauthorised removal by a retaining bracket (electrical safety) at the bottom left. Always secure the outer case with this bracket again after refitting.

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6 720 610 602 GB (03.02)

Installation

B Lift off the top fixing lugs and slide the case forwards

and remove (3).

Fig. 13

Fixing the appliance

B Fit the washers onto the gas and water connections. B Lift the boiler onto the wall-mounting frame. The lugs

pass through the rectangular holes in the boiler back panel.

B Take care not to disturb the washers on the connec-

tions.

Connecting the flue duct

B Fit flue duct connector onto appliance flue spigot. B Secure with the two screws supplied.

Fig. 14

B For remaining installation of flue assembly, refer to

the relevant installation instructions.

3.8 Checking the connections

Water connections

B Check that the O-rings or seals are in place before

tightening the connection.

B Turn on the service valves for central heating flow

and return and fill the heating system through a WRAS approved filling loop.

B Check all seals and unions for leaks (testing pres-

sure max. 3.0 bar as indicated by pressure gauge).

B Turn on cold water service cock and fill hot water

system (testing pressure max. 10 bar).

B Check all connections for leaks.

Gas supply pipe

B Check that the seal is in place before tightening the

connection.

B Turn off gas cock to protect gas valve against dam-

age from excessive pressure.

B Check gas supply pipe. B Release the pressure on the gas supply pipe.

3.9 Flue Systems

The only flue systems that may be used are those supplied with the boiler. The flue system must be installed in accordance with the requirements of BS5440:1.

Standard 100 mm flue system

The standard concentric flue system provides for a horizontal length of upto 4 m. Full instructions for fitting this flue are in Subsection 3.9.2 “Installation of the flue”.

Alternative 125 mm diameter flue systems

Installation instructions for the alternative flue systems are sent with the appropriate flue kit.

Systems are available to give a maximum horizontal length of 13 m (ZWBR 8-30) and 10 m (ZWBR 11-37).

A vertical flue system upto a height of 15 m (ZWBR 8-

30) and 12 m (ZWBR 11-37) is available. 45° and 90° flue bends can be used with a correspond-

ing reduction in flue length of 2 m for each 90° bend and 1 m for each 45° bend used.

IMPORTANT: Any horizontal flue system fitted to a condensing boiler must incline towards the appliance at an angle of 3 % (30 mm per metre length) to prevent condensate dripping from the flue terminal. This

means that the clearance above the appliance must be increased to match the duct length. Refer to fig. 1 on page 5.

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6 7 2 0 6 1 0 3 3 2 - 0 9 . 2 R

1 .

2 .

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Installation

3.9.1 Siting the Flue Terminal

The flue must be installed in accordance with BS 5440:1 and the Building Regulations. Flue terminals in carports and under balconies are to be avoided. The terminal must be positioned so that it does not cause an obstruction nor the combustion products a nuisance. See fig. 15 and table 9. The terminal will, at times, give out a plume of water vapour and consideration must be given to this when choosing a terminal position. Keep clear of security

lighting, activated by passive infra-red sensing heads. If the terminal is less than 2 m above a surface to which people have access then a guard must be fitted. The guard must be evenly spaced about the terminal with a space of 50 mm in each direction and fixed with plated screws. A guard Type K6 for the standard horizontal flue, can be obtained from Tower Flue Components, Vale Rise, Tonbridge TN9 1TB.

Fig. 15

Minimum dimensions of flue terminal positions (all types) (see fig. 15)

Dimension Terminal Position (kW input expressed in net) Balanced ﬂ ues room sealed: Fanned draught

Directly below an opening, air brick, opening windows, etc. 300 mm

Above an opening, air brick, opening window, etc. 300 mm

Horizontally to an opening, air brick, opening window, etc. 300 mm D Below gutters, soil pipes or drain pipes 75 mm E Below eaves 200 mm F

Below balconies or car port roof (lowest point) 200 mm G From a vertical drain pipe or soil pipe 150 mm H From an internal or external corner 300 mm I Above ground roof or balcony level 300 mm J From a surface facing the terminal 600 mm K From a terminal facing the terminal 1200 mm L From an opening in the car port (e. g. door, window) into the dwelling 1200 mm M Vertically from a terminal on the same wall 1500 mm N Horizontally from a terminal on the same wall 300 mm O From the wall on which the terminal is mounted Not applicable P From a vertical structure on the roof Not applicable Q Above intersection with roof Not applicable

Table 9

1) In addition, the terminal should not be nearer than 150 mm (fanned draught) to an opening in the building fabric formed for the purpose of accommodating a built-in element such as a window frame.

2) Not recommended.

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Installation

3.9.2 Installation of the flue

The standard 100 mm diameter horizontal flue system is suitable for lengths upto 4 m. Flues upto 650 mm do not require an extension duct assembly. Flues between 1600 mm and 4000 mm require extension duct assemblies. NOTE: Flue lengths between 650 mm and 730 mm cannot be accomodated. Refer to fig. 17, 18, 19.

Standard system comprise: Flue turret - Flue turret clamp - Terminal assembly - Wall sealing - plates. Extension kit comprises: Air duct - Flue duct - Duct clamp. Refer to fig. 20.

Instructions for fitting other flue systems are packed with the relevant flue kit. Check that the position chosen for the appliance is satisfactory. Refer to fig. 16.

Fig. 16 Marking the position of the side flue opening

Fig. 17 Standard Flue

Appliance

120

Drilling point for flue duct opening

3 %

(30 mm/metre)

Centre line of flue opening and appliance

Centre line of flue/air duct

Top of the

wall

mounting

frame

H Standard Horizontal Flue 158 mm Optional Horizontal Flue 121 mm

6 720 610 602-07.2O

Flue Turret

No Clamp

Maximum 650 mm

Terminal Assembly

Outer Wall

6 720 610 602 - 08.1O

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Installation

Fig. 18 Flue with One Extension

Fig. 19 Flue with Extensions

Fig. 20 Flue Components

Maximum 1600mm

Flue Turret

No Clamp

Terminal Assembly

Outer Wall

Extension Duct

6 720 610 602 - 09.1O

Clamp

Flue Turret

No Clamp

Clamp

Extension Duct

Clamp

Extension Duct

Terminal Assembly

Outer Wall

6 720 610 602 - 10.1O

Extension Air Duct

Extension Flue Duct

Terminal Assembly

Duct Clamp

Wall Sealing Plates

6 720 610 602 - 11.1O

Flue Turret

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Installation

3.9.3 Flue duct preparation and assembly

Measure the flue length L. Refer to fig. 21, 22.

Fig. 21 Flue length - rear

Fig. 22 Flue length - side

Mark off the lengths shown onto the ducts and cut to length. The cuts must be square and free from burrs. Terminal assembly outer (air) duct - L- 70 mm, inner (flue) duct - L- 50 mm.The measurement is made from the ridge at the terminal indicating the outer face of the wall. Refer to fig. 23. Extension air duct - L- 70mm, flue duct - L- 50 mm. The measurement is from the formed end.

Fig. 23 Flue terminal position

Assemble flue system completely. Push the ducts fully together and clamp in the positions. The slope of the terminal outlet must face downwards.

The assembly will be made easier if a solvent free grease is lightly applied i.e Vaseline, to the male end of the ducts.

NOTE: An inner wall sealing plate is provided which should be fitted to the ducts before assembly.

Push the assembly through the wall and fix the turret to the appliance with the clamp. Refer to fig. 24.

Fig. 24 Flue turret

Ensure that the turret is fully entered into the socket on the boiler. From the outside fix the outer wall plate to the terminal and, after ensuring the duct is properly i nclined towards the boiler, fix the plate to the wall.

If the terminal is within 2 m of the ground where there is access then an approved terminal guard must be fitted. The guard must give a clearance of at least 50 mm around the terminal an be fixed with corrosion resistant screws.

NOTE: THE FLUE MUST BE INCLINED T O THE

BOILER

120

6 720 610 602 - 12.1O

NOTE: THE FLUE MUST BE INCLINED T O THE

BOILER

6 720 610 602 - 13.1O

Outer Wall Face

Flue Terminal

Raised Ring locating the terminal relative to the outside wall face

6 720 610 576 - 20.1O

Air and Flue Duct Entry into silicone rubber seals

Flue Turret

Clamp

Flue Socket on Boiler

6 720 610 602 - 14.1O

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Electrical connections

4 Electrical connections

All control and safety systems are built into the appliance.

B Allow mains cable to protrude at least 50 cm from

wall.

B To make splash-water proof (IP): cut the cable grom-

met hole size to match diameter of cable, see fig. 27.

It must be possible to isolate the appliance. The appliance must be earthed.

The appliance must be connected to the mains through a 6 A double pole isolator with a contact separation 3 mm in all poles and supplying the appliance and controls only. The wiring must comply with the current requirements of the IEE Wiring Regulations and any local regulations which apply.

• Supply: 230 V ~ 50 Hz, 140 Watts

• Mains cable: PVC insulated 0.75 mm2

(24 x 0.20 mm) to BS6500-Table 6. Temperature rated 100˚C.

• Protection IPX4D

• External fuse 3 A.

4.1 Connecting the appliance

To gain access to the mains connection remove the drop down facia cover. The drop down cover is removed by lowering it to the horizontal position and pushing firmly upwards at the rear of the supports to release the cover. Lift cover from the appliance.

After installation (or in the event of an electrical fault) the electrical system shall be checked for short circuits, fuse failure, incorrect polarity of connections, earth continuity and resistance to earth.

B Pull out cover panel at the bottom and remove. Refer

to fig. 25.

Fig. 25

B Remove screw and slide terminal cover forwards to

remove. Refer to fig. 26.

Fig. 26

B Always disconnect the power supply to

the appliance at the mains before carrying out any work on the electrical systems and components.

6 720 610 332-10.1R

6 720 610 336 -18.1R

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6 720 610 602 GB (03.02)

Electrical connections

B Cut cable grommet to diameter of cable.

Fig. 27

B Feed cable through cable grommet and connect the

mains supply cable, see fig. 28.

B Secure cable in cable grommet by means of cable

grip.

Fig. 28

4.2 Connecting TR2 Room thermostat

The TR2 should be connected to terminals 3, 4 and F beneath the Textdisplay, page 8, fig. 4, item 422.

4.3 Mains Voltage external controls connections

Fig. 29

Note: If an external timer is used then the domestic hot water pre-heat facility can only be isolated by actuating the ECO-button.

6 720 610 332-12.1R

13-14

10-12

8-9

5-7

4130-14.1R

230 V R

oom Thermostat Connections

ST8

Remove Link

Neutral

Liv

Swit

ched Liv

Neutr

Live

Swit

ched Live

Motor

230 V Pr

ogrammer Connections

230 V r

oom thermostat and

Programmer Connections

ST8

Neutral

Live

eutr

Live

Swit

ched Liv

Motor

Series connection to be made

safe

NOTE: Only double insulated controls not requiring an earth can be used

6 720 610 576 - 22.1O

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Commissioning

5 Commissioning

Fig. 30

8.1 Pressure gauge 15 Safety valve 27 Automatic vent 61 Reset button 135 Master switch 136 Temperature control for central heating 170 Service cocks on CH flow and return 171 Hot water 172 Gas cock (shown in off position) 173 Cold water service cock 295 Appliance type sticker 310 Temperature control for hot water 317 Multifunction display 358 Condensation trap 363 Indicator lamp for burner 364 Indicator lamp for power supply 365 “Chimney sweep” button 366 Service button 367 ECO button 400 Textdisplay

5.1 Commissioning

Benchmark Water Treatment: For optimum performance after installation, this boiler and its associated central heating system should be flushed in accordance with the guidelines given in BS7593:1992 - Treatment of water in domestic hot water systems. Full instructions are supplied with proprietary cleansers sold for this purpose. If an inhibitor is to be used after flushing, it should be used in accordance with the inhibitor manufacturers instructions.

To drain the appliance shut the system valves and open the system drain point.

Suitable flushing agents and inhibitors are available from Betz/Dearborn Tel.: 0151 4209563, Fernox Tel.: 01799 550811 and Salamander Tel.: 0121 378 0952. Instructions for use are supplied with the these products.

ECO

364

135

295

8.1

365

317 366 367

310

136

363

400

358

6 720 610 597 - 05.1O

170

171

173

170

172

Never run the appliance when empty or unpressurised.

The operational CO2 level is set at the factory and no adjustment is necessary when installing a natural gas fired appliance.

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Commissioning

B Before commissioning, the gas supply pres-

sure must be checked at the gas supply pressure test point (see page 6, fig. 2, item 7). Natural gas appliances must not be operated if the gas supply pressure is below 18 mbar or above 24 mbar. LPG appliances must not be operated if the supply pressure is not 37 mbar at the inlet to the appliance.

B Unscrew the condensation trap (358) and pull out,

fill with approx. 1/4 l of water and refit. Refer to fig. 30.

B Adjust charge pressure of expansion vessel to static

head of the central heating system (see page 31).

B Open all system radiator valves. B Turn on service valves (170), fill central heating sys-

tem to pressure of 1 - 2 bar through the WRAS approved filling loop. Refer to fig. 30.

B Vent radiators. B Refill heating system and set the pressure to 1 bar. B Turn on cold water service cock (173). Refer to

fig. 30.

B Check that the gas type specified on the identifica-

tion plate matches that of the gas supply.

B Turn on gas cock (172). Refer to fig. 30.

5.2 Switching the appliance on/off

Switching on

B Switch on the appliance at the master switch (I).

The indicator lamp shows green and the display will show the central heating flow temperature, when the appliance is operating in the central heating mode.

Fig. 31

The trap filling programme ensures that the condensation trap is filled after the appliance has been installed or after the appliance has been out of use for a long period or the mains supply has been interrupted. For that reason, the appliance remains at minimum heating output for 15 minutes.

B Open automatic vent (27) and re-close after venting

(page 22).

Switching off the appliance

B Set the master switch to (0).

The green indicator lamp goes out. The optional timer will continue running until the emergency supply is exhausted.

5.3 Switching on the central heating

The central heating flow temperature is adjustable between 35˚C and 88˚C. Refer to table 12, page 31.

B Turn the temperature control to set the flow tem-

perature to a level appropriate to the type of central heating system:

– Underfloor heating: e.g. setting “3”

(approx. 50˚C)

– Low-temperature heating: setting “E”

(approx. 75˚C)

– Central heating systems for flow temperatures up

to 88 °C: limited “max” setting for low-temperature operation (see page 31).

When the burner is alight, the red indicator lamp lights up.

Fig. 32

5.4 System controls

B Set room thermostat to the desired room tempera-

ture.

B Set outside- temperature driven control unit, if fitted.

Refer to the instructions with the control.

B Set the thermostatic radiator valves to the desired

settings.

If the display alternates between -II- and the central heating flow temperature, the trap filling programme is active.

6 720 610 333-04.1O

B Always disconnect the appliance from

the power supply (fuse, circuit breaker) before carrying out any work on the electrical systems or components.

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Commissioning

5.5 Setting the domestic hot water temperature and flow rate

5.5.1 Domestic hot water temperature

The hot water temperature can be set to between approx. 40 °C and 60 °C.

This temperature is not shown on the display.

Fig. 33

“ECO” button

By pressing and holding the “ECO” button , until the display lights, you can switch between Comfort mode and Economy mode.

Comfort mode: button is not lit (factory setting)

The appliance is held constantly at the set temperature. This means that hot water is available almost instantaneously at the tap. Consequently the appliance will switch on at intervals, even if no hot water is being drawn.

ECO mode with demand detection, button is lit

The demand detection function enables maximum gas and water economy. Briefly turning a hot water tap on and then off again signals demand to the appliance which then heats up the water to the set temperature. Hot water is thus available in about 1 minute.

ECO mode, button is lit

Water is not heated up until hot water is drawn. This means that there is a longer waiting period before hot water is available.

5.5.2 Hot water flow rate

The flow rate is factory set to 8 l/min. Under standard conditions (2 bar) supply pressure, one

full turn is equivalent to approximately 2 l/min.

B To increase the flow rate (max. 14 l/min):

turn screw on flow switch anti-clockwise (+). The outlet temperature will decrease relative to the increase in the flow rate.

B To reduce the flow rate (min. 8 l/min):

turn screw on flow switch clockwise (–). The outlet temperature will increase relative to the decrease in the flow rate.

Fig. 34

5.6 Summer mode (hot water only)

With room thermostat

B Turn temperature control on the appliance anti-

clockwise as far as the stop. The central heating is now turned off. The hot water function and the mains power supply for the heating programmer and timer remain switched on.

5.7 Frost protection

B Leave master switch switched on.

If the appliance is to be left for long periods switch the central heating off:

B Add a suitable anti-freeze fluid to the water in the

central heating system. Suitable products are available from Betz-Dearborn Tel.: 0151 4209563 and Fernox Tel.: 01799

550811.

5.8 Pump anti-seize function

Every time the pump is switched off, a timer is started. If after 24 hours the pump has not run again, it is switched on for a period of 10 seconds.

Setting Hot Water temperature

Turn fully anti-clockwise approx. 40˚C

 approx. 55˚C

Turn fully clockwise approx. 60˚C

Table 10

6 720 610 333-07.1O

Frost protection and constant frost protection modes can be set on the text display module.

This function prevents the central heating pump seizing after long periods of inactivity.

6720 610 332-25.1O

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Commissioning

5.9 Fault Condition

In the unlikely event of a fault occuring while the appliance is in operation:

The display and the textdisplay then show a fault code and the button may also flash.

If the button flashes: B Press and hold the button until the display shows

“– –”. The appliance will then start up again and the display

will show the central heating flow temperature. If the button does not flash: B Switch the appliance off and then on again at the

master switch.

The appliance will start up again and the central heat-

ing flow temperature will be displayed.

A list of faults that may occur is given on page 46.

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6 720 610 602 GB (03.02)

Text Display

6 Text Display

6.1 General Description

• The text display is used to display information about

the appliance and the system and to alter the settings displayed.

• Once the appliance has been in operation for one

day, the text display module has a power buffer period of about 10 hours during which it will run without the mains power supply. After that period has elapsed, the clock function shuts down but all other settings are retained.

6.2 Programming

Fig. 35 Controls

a Display b “Up”/“More” button c “Down”/“Less” button d “Back” button e “Next” button f “Delete” button

The standard display shows the following information:

• Time

• Room temperature (if TR 2 connected)

• CH flow temperature

• Domestic Hot Water temperature (ZSBR if a Stor-

age Tank is accorded).

Additional indication if a special programme is active:

• x holidays

• Hot water immediately

• Constant on (comfort, if TR2 is not connected)

• Constant off (economy, if TR2 is not connected).

Other special operating modes may be displayed during commissioning, servicing, etc.

The programming procedure is described in detail below using the clock function as an example:

B To start programming, press any button, e. g. .

The display lighting switches on and the main menu is displayed:

Fig. 36 Main menu

B Use the or button to move the cursor

arrow on the left of the menu so that it points to the desired menu item. In this example, the cursor is positioned next to the menu item Time/day/holidays.

B Confirm the selection by pressing the button.

The corresponding submenu is displayed:

Fig. 37 Submenu: Time/day

In the submenus, the top line indicates what action is required. The bottom line shows the previous menu level, if applicable (see fig. 38).

B Use the or button to select Time/day. B Confirm the selection by pressing the button.

The corresponding submenu is displayed:

Fig. 38 Setting the hour

When settings are being entered, the setting to be altered is indicated on the top line. In addition, the setting being altered is displayed with a dark background.

B Use the or button to set the hour.

– Press and release to change the display by one

unit at a time

– Press and hold to change the display rapidly

B Confirm the setting by pressing the button.

B Use the or button to set the minutes. B Confirm the setting by pressing the button. B Use the or button to set the day of the

week.

6 720 610 337-08.1R

6 720 610 598-04.2O

/holidays

6 720 610 598-05.2O

6 720 610 598-06.2O

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Text Display

B Press the button to confirm the setting. The

cursor then returns to the top line.

-or-

B Press the button to confirm the setting and

return to the previous menu (fig. 37 page 26).

-or-

B Do not press any other buttons for 15 minutes.

6.2.1 Deleting a setting

Either overwrite the setting or press the button to delete it.

B Find the setting to be deleted. B Press and release the button.

The display shows --:--

6.2.2 Resetting all parameters to their original

settings

B Press and hold the button for more than 15 sec-

onds.

After about 5 seconds, the following message

appears on the display:

ATTENTION

Delete all parameters

in x seconds

Once the reset has been completed, the following

message is displayed:

Please wait... Initialising

6.3 Menu structure

The hours of service can not be reset to 0.

Submenu

Main menu 1. 2. 3.

Parameters to change/select

Page

Time/ day/holidays

Time/day - - - Hours

- Minutes

- Day of week

Holidays - - Days holiday 28

Heating Heating

program

- - - Day

- 1st operating mode

- 1st switching point ...

- 6th switching point

Set economy temp. (if TR2 is connected)

- - 5...30˚C 28

Manual (if TR2 is not connected)

- - - Automatic

- Constant on (comfort)

- Constant off (economy)

Hot water

Hot water program

- - - Day

- 1st operating mode

- 1st switching point

...

- 6th switching point

Hot water immediately

- - Off/On 29

Info - - - - 29 Settings Heating - - Optimum Start Off/On 30

Hot water (ZSBRmodels)

- - Only charging times/ times and temperatures

Service Display

service param.

- - 30

Further options

Language

-English/

-Français/

-Deutsch

-Time correction

-LCD contrast

30 30

Operating times

- 30

Fault history

- 30

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6 720 610 602 GB (03.02)

Text Display

6.4 Setting the time/day

6.4.1 Setting the time and day

For details of how to set the time and day, refer to page 26.

6.4.2 Holidays

In the Holiday programme, the central heating runs in Economy mode and the hot water is switched off (frost protection function remains active).

B From the main menu, select Time/day/holidays,

and from the first submenu select Holidays.

B Enter the number of days holiday by pressing or

(max. 99 days holiday). After the set number of days, the text display module automatically cancels Economy mode at midnight on the last day and returns to Automatic mode.

To cancel Holiday mode early: B In the Holidays submenu:

Press the button until the display shows 0 .

6.5 Heating

6.5.1 Heating programme

Basic setting (Automatic mode)

• The appliance switches automatically between nor-

mal heating, Economy mode and Frost protection mode according to the timer settings entered.

• Basic setting: – Heating starts at 6:00 am – Economy starts at 10:00 pm

Setting options

• Maximum of six switching points per day with three different operating modes (Heating, Economy, Frost protection).

• Same times for Monday to Friday.

• Same times for Saturday and Sunday.

• Different times for every day.

Setting switching times and operating mode

B From the main menu select Heating and then from

the first submenu, select Heating program.

B Select Monday - Friday, Saturday and Sunday or

an individual day of the week. – Monday - Friday: to have “Heating” and “Econ-

omy” or “Frost protection” switching on at the same times every weekday.

– Saturday - Sunday: to have “Heating” and

“Economy” or “Frost protection” switching on at the same times Saturday and Sunday.

– Individual day of the week (e. g. Thursday): to

have the relevant program always switching on at the specified time on that day of the week, i.e. “Heating”, “Economy” or “Frost protection” at the same time every Thursday.

B Press . The display shows Set 1. operating

mode.

B Set the desired first operating mode (Heating, Econ-

omy or Frost protection).

B Press . The display shows Set 1. time period. B Set the desired first time period. B Press . Set the following operating modes and

time periods as described for the first.

B If necessary: select the next day and enter the oper-

ating modes and timer periods as described above.

Timer periods and operating modes are you do not wish to change can be skipped by pressing .

6.5.2 Setting the Economy temperature (if TR2 is connected)

This option allows you to set the room temperature for Economy mode (Off (Economy)).

This function is only active if:

• Automatic mode or Economy mode is set on the TR

2 room thermostat.

B From the main menu, select Heating and then from

the first submenu, select Set Economy temp..

B Use the or button to set a temperature

between 5 and 30 ˚C.

Changing winter and summer time:

B Only adjust the clock! Do not alter the

switching points (for heating, economy, etc.).

The day on which you enter the days holiday counts as the first day of the holiday, i.e. the unit starts the holiday program immediately. Only include the day on which you are returning if you don’t want the heating to return to the normal program on that day!

If the settings for a particular day of the week are different from the settings for the other days, then if Monday - Friday or Saturday and Sunday is selected, the display shows

--:--, i.e. there are no common switching points for those options.

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6 720 610 602 GB (03.02)

Text Display

6.5.3 Manual operating mode (if TR2 is not connected)

For selecting an operating mode that is different from the one set in the heating programme (Automatic mode).

• You can choose between Automatic, Constant on

(comfort) and Constant off (economy).

• The manually selected operating mode starts imme-

diately.

• Constant off (economy) and Constant on (comfort)

are automatically reset at 00.00 (midnight).

• To cancel the manually selected operating mode:

– select the relevant menu and then press the

button,

– or select a different operating mode, – or set Holiday.

B From the main menu select Heating and then from

the first submenu Manual select required mode.

6.6 Hot water

General description

• Combi models only: The basic settings provide a

straightforward timer programme: enabled from 5:00 am, disabled from 10:00 pm. The ECO button must not be lit (Comfort mode).

• ZSBR models (with Storage Tank): The basic

settings provide a timer programme: enable from 5:00 am, disable from 10:00 pm. With the menu Hot water (see page 29) you can choose a timer-/temperature programme with the basic settings: 60˚C from 5:00 am, 10˚C from 10:00 pm.

6.6.1 Hot water programme

• Up to six switching points per day can be set.

• There are two operating modes: Blocked and

Released.

B From the main menu, select Hot water and then

from the first submenu, select Hot water program.

B Set the days of the week, Blocked/Released (oper-

ating mode) in the same way as for the switching points and modes for heating as described on page 28.

6.6.2 Hot water immediately

• Hot water immediately ON:

– Comfort mode is active for 2 hours.

• Comfort mode is active for 2 hours: normal auto-

matic program (Hot water mode according to timer programme entered).

B From the main menu, select Hot water and then

from the first submenu, select Hot water immedi- ately.

B Press or to switch Hot water immedi-

ately on or off.

6.7 i Info

B Select Info from the main menu.

You can view the following information:

Display text Description

Room temperature

(if TR 2 connected)

Current temperature in the room where TR 2 is installed

Required room temperature

(if TR 2 connected)

Required temperature in room where TR 2 is installed

Operating mode

(if TR 2 connected)

E. g. Heating, Economy in Automatic mode or Economy, Heating, Frost protection in manual mode

Max. flow temp. Maximum CH flow tempera-

ture set on the temperature control for CH flow

Actual flow temp. Actual CH flow temperature Required flow

temp.

Required CH flow temperature

Max HW temp. Maximum permissible hot

water outflow temperature

Required HW temp.

Required hot water temperature

Actual HW temp. Actual hot water outflow

temperature

Storage Tank charge released or blocked

Shows, if hot water is released or blocked

Storage Tank charge on or off or Storage Tank charge afterrunning

Shows, if hot water is on or off, or if the pump for the Storage Tank afterrunning is on

Boiler operat. mode winter/ summer

Indicates which mode the CH flow temperature control is set to

Burner on/off Indicates whether the

burner is alight or not

Pump on/off Indicates whether the inte-

gral pump is switched on or off

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6 720 610 602 GB (03.02)

Text Display

6.8 Settings

6.8.1 Heating (if TR 2 is connected)

Optimum Start

B From the main menu, select Settings and from the

first submenu, select Heating.

B Press or to switch Optimum Start on or off.

Basic setting: “ON”

6.8.2 Hot Water (Storage Tank, ZSBR models only)

The text display can control the hot water either with Times and temperatures or only times.

• Times and temperatures: One can choose up to

six different times with temperatures, see page 29 “Hot water”.

• Only times: During that times the Storage Tank will

be charged to the choosed temperature.

B From the main menu, select Settings and from the

first submenu select hot water.

B Press or to switch Times and temperatures

or only times.

6.8.3 Service

Displaying service functions

This option displays various current settings and statuses of the electrically controlled appliance and system components for the benefit of the heating engineer.

Service parameters

Language Available languages are: English, Français (French), Deutsch (German).

B From the main menu, select Settings, from the first

submenu select Service, from the Second submenu select Further options, and from the third submenu select Language.

B Press or to select the desired language.

Two other supplementary functions can be selected from the third submenu Language:

• Time correction

• LCD contrast.

Time correction: B Press and hold the button (about 5 seconds)

until the display shows Time correction and LCD contrast.

B Press or to select Time correction.

B Press the button. The display shows Change

value.

B Press or to set the number of seconds in

24 hours.

Basic setting: “+ 0 s” LCD contrast:

B Press and hold the button (about 5 seconds)

until the display shows Time correction and LCD contrast.

B Press or to select LCD contrast. B Press the button. The display shows Change

value.

B Press or to adjust the LCD contrast.

Basic setting: e. g. “47”

Operating times This option shows the hours of service (appliance, burner and hot water) since commissioning.

B From the main menu, select Settings, from the first

submenu select Service, from the Second submenu select Further options, and from the third submenu select Operating times.

Fault history This option displays any faults that have occurred for the information of the service engineer. The first fault displayed may still be active. Any other faults displayed are no longer active.

B From the main menu, select Settings, from the first

submenu select Service, from the Second submenu select Further options, and from the third submenu select Fault history.

6.9 Individual timer programmes

Tables for your own timer programmes you find in the User Manual.

Turn the hot water temperature control always higher than the temperature at the text display is choosen.

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6 720 610 602 GB (03.02)

Individual settings

7 Individual settings

7.1 Mechanical settings

7.1.1 Checking the size of the expansion vessel

Maximum pressure at maximum CH flow temperature is

2.5 bar. If the pressure is greater than this then fit an extra expansion vessel. Refer to table 11.

System Capacity – BS7074:1

7.1.2 Setting the central heating flow temperature

The central heating flow temperature can be set to between 35˚C and 88˚C.

Limited maximum setting for low-temperature operation

The temperature control is factory limited to setting E, giving a maximum flow temperature of 75˚C.

Adjustment of the heating output to the calculated heat demand is not required by the heating systems regulations.

Removing the maximum setting limit

For heating systems which require higher flow temperatures, the maximum setting limit can be removed.

B Lift off the yellow button on the temperature control

with a screwdriver.

Fig. 39

B Rotate yellow button through 180° and replace (dot

facing inwards). The CH flow temperature is no longer limited.

7.2 Settings on the Bosch Heatronic

7.2.1 General description

The text display module provides a convenient means of setting various appliance functions.

This description is limited to those functions necessary for commissioning.

Displaying service functions

All service functions are displayed.

B Press any button to activate the main menu. B Press or button until the arrow cursor is

pointing to Settings.

B Press the button. B Press or button until the arrow cursor is

pointing to Service.

B Press the button. B Press the button to select Display service

parameters. Service function 0.0, Last fault is displayed.

B Press the or button to cycle through the

current settings.

B Press the button to exit the menu.

Expansion Vessel Pressure and System Capacity

Expansion Vessel litres 10

Expansion Vessel Charge Pressure

bar 0.75

System pressure and capacity

1 bar litres 82

1.5 bar litres 46

Table 11

With underfloor heating systems, observe the maximum permissible flow temperatures.

6 720 610 332-27.1O

Control setting CH flow temperature

1 approx. 35˚C 2 approx. 43˚C 3 approx. 51˚C 4 approx. 59˚C 5 approx. 67˚C

E approx. 75˚C

max approx. 88˚C

Table 12

Service function Code no.

see page

Anti-cycle time 2.4 32 Max. CH flow temp. 2.5 32 Max. heating output 5.0 32 Constant hot water cycle-

time

6.8 32

Variable pump settings 7.0 32

Table 13

For a detailed description, refer to Service Booklet for the Engineer 7 181 465 347.

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6 720 610 602 GB (03.02)

Individual settings

Setting service functions

Only the service functions that can be set are displayed.

B Press any button to activate the main menu. B Press or button until the arrow cursor is

pointing to Settings.

B Press the button. B Press oder button until the arrow cursor

is pointing to Service.

B Press the button.

The cursor is pointing to Display service parame- ters.

B Press and hold the button (for about 5 sec-

onds) until the display shows Adjust service parameters and the first service function to be set, e.g. 2.0, Operating mode. If a fault has occurred, the display will show 0.0 and the last fault.

B Press the or button until the desired

service function is displayed.

B Press the button.

The first line of the display shows Change value.

B Use the or buttons to enter the required

setting.

B Press the button.

The text display shows ATTENTION Store set- tings?.

B Press or to select yes or no. B Press to confirm your selection.

The text display shows Please wait ... ..., and the

service function is then displayed with the new setting.

B Press the or button until the next func-

tion you wish to change is displayed.

-or-

B Press the button to exit the menu.

7.2.2 Setting the anti-cycle time (Service Function 2.4)

This service function is only active if Service Function

2.7, automatic anti-cycle time, is deactivated.

The anti-cycle time can be set to between 0 and 15 minutes (is factory set to 3 minutes).

If the setting 0 is entered, the anti-cycle time is inactive. The shortest possible anti-cycle time is 1 minute (rec-

ommended for single-pipe and hot-air heating systems).

7.2.3 Setting the maximum CH flow temperature (Service Function 2.5)

The maximum CH flow temperature can be set to between 35˚C and 88˚C (factory setting).

7.2.4 Setting the heating output (Service Function 5.0)

The heating output can be set to any level between min. rated heat output and max rated heat output to limit it to the specific heat requirements.

The factory setting is the max. rated heat output, 100 %. B Look up heating output in kW and corresponding

code number on the settings tables for heating output (see page 48).

B Enter the code number on the text display module. B Measure the gas flow rate and compare with the fig-

ures specified for the code number shown. If different, correct code number.

7.2.5 Constant hot water cycle time (Service Function 6.8)

In Comfort mode “ECO light off”, the hot water inside the appliance is held constantly at the set temperature. For that reason, the appliance switches on if the water temperature falls below a certain temperature. In order to prevent it switching on and off too frequently, the constant hot water cycle time service function allows you to set the minimum period between switching off and on again. This function has no effect on normal demand for hot water and relates only to the constant hot water function in Comfort mode.

The cycle time can be set to any period between 20 and 60 minutes (is factory set to 20 minutes).

7.2.6 Variable pump settings (Service Function 7.0)

The pump speed varies automatically to match the water flow requirement of the system determined by the position of thermostatic radiater valves. An automatic by-pass must not be used.

The Service Function 7.0 is factory set to 4 which will accommodate the majority of heating systems.

Information on the re-settings of this functions can be found in the Service Booklet for the Engineer number 7 181 465 347.

7.3 Setting the gas/air ratio

The appliance is set at the factory and adjustment is not necessary.

If the appliance is connected to an outside-temperature controlled heating programmer, the anti-cycle time does not need to be set on the appliance and is optimised by the programmer instead.

The full rated heat output is still available for hot water or charging the hot water cylinder even if the heating output has been limited.

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6 720 610 602 GB (03.02)

Converting the appliance to different gas types

8 Converting the appliance to different gas types

The setting is factory sealed at maximum. Adjustment to the rated heat input and min. heat input is not necessary.

Checking the gas supply pressure

B Check the gas supply pressure at the gas supply

pressure testing point.

Natural gas

• Appliances for natural gas type G20 are factory set

to Wobbe-Index 15 kWh/m3 and 20 mbar supply pressure and sealed.

Conversion kits

• Instructions are sent with each conversion kit.

8.1 Setting the gas/air ratio

The gas/air ratio may only be adjusted on the basis of a CO2 measurement at max. heat output and min. heat output using an electronic tester.

B Switch off the appliance at the master switch (O). B Remove the outer case (see page 15, refer to

fig. 13).

B Switch on the appliance at the master switch (I). B Unscrew sealing plug from flue gas testing

point (234). Refer to fig. 40.

B Insert testing probe about 135 mm into the flue gas

testing point and seal testing point.

Fig. 40

B On the text display unit, select in the main menu Set-

tings, Service, Display service parameters.

B Press and hold the button (for about 5 sec-

onds) until the display shows Adjust service

parameters and the first service function to be set,

2.0 Operating mode. If a fault has occurred, the

display will show 0.0 and the last fault.

B Press or until the display shows 2.0

Operating mode normal.

B Press the button. B Press or to select Max. B Measure the CO2 level. B Prise off the seal on the gas flow restrictor.

Natural gas appliances must not be operated if the gas supply pressure is below 18 mbar or above 24 mbar.

LPG appliances must not be operated if the supply pressure is below or above 37 mbar.

Model

For conversion from ... Order no.

ZWBR 8-30 N.G to L.P.G 7 710 149 050

ZWBR 11-30 L.P.G to N.G 7 710 239 086

ZWBR 14-37 L.P.G to N.G 7 710 239 087

ZWBR 11-37 N.G to L.P.G 7 710 149 052

Table 14

6 7 2 0 6 1 0 3 3 2 - 5 7 . 2 R

2 3 4

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6 720 610 602 GB (03.02)

Converting the appliance to different gas types

B Adjust the gas flow restrictor (63) to obtain the CO2

level given in Table 15. Refer to fig. 41.

Fig. 41

B Press or to select Min. B Measure the CO2 level. B Remove the seal from the gas valve adjusting

screw (64) and adjust the CO2 level to the figure given in Table 15 for min. rated heat output. Refer to fig. 42.

Fig. 42

B Recheck the levels at min. and max. rated heat output

and re-adjust if necessary.

B Press or until the display shows

normal.

B Press the button. The text display shows

Store settings.

B Press to select yes. B Press the button. B Remove testing probe from the flue gas testing

point (234) and refit sealing plug.

B Re-seal gas valve adjusting screw and gas flow

restrictor.

B Replace the outer case by locating it on the top lugs

and pushing backwards until the bottom clips are fully engaged. Check that the case is properly aligned with facia. Refer to fig. 13.

B Secure by replacing the screw at the bottom left.

Refer to fig. 13.

ZWBR 8-30

Gas Type

CO2 reading at max. rated heat output

CO2 reading at min. rated heat output

Natural gas type G20

9.4 % 9.2 %

LPG G31 (propane)

11.0 % 11.0 %

Table 15

ZWBR 11-37

Gas Type

CO2 reading at max. and min. rated heat output

Natural gas type G20

9.2 %

LPG G31 (propane)

11.0 %

Table 16

6 720 610 332-64.1R

3928-74.1R

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Converting the appliance to different gas types

8.2 Testing combustion air/flue gas at set heat output

8.2.1 Testing the O2 or CO2 level in the combustion air

B Press and hold the button until the display

shows – –. “Chimney sweep” mode is now active. The button will light up and the display shows the CH flow temperature.

B Remove sealing plug from combustion air testing

point (234.1, fig. 43).

B Insert testing probe about 80 mm into the testing

point and seal testing point.

Fig. 43

B Measure O2 and CO2 levels. B Refit sealing plug. B Press and hold button until the display shows – –.

The button will stop flashing and the display shows the CH flow temperature.

8.2.2 Testing CO and CO

B Press and hold the button until the display

shows – –. “Chimney sweep” mode is now active. The button will light up and the display shows the CH flow temperature.

B Remove sealing plug from flue gas testing point

(234, fig. 43).

B Insert testing probe about 135 mm into the testing

point and seal testing point.

B CO- and CO2 levels. B Refit sealing plug. B Press and hold button until the display shows – –.

The button will stop flashing and the display shows the CH flow temperature.

By testing the O2 or CO2 level in the combustion air the gas tightness of a type C13, C33 flue system can be checked. The O2 level must not be less than 20,6 %. The CO2 level must not exceed 0,2 %.

In “chimney sweep” mode, the appliance switches to max. rated heat output or the set heating output. You then have 15 minutes in which to measure the levels. After that, the appliance switches back from “chimney sweep” mode to normal mode.

6 7 2 0 6 1 0 3 3 2 - 6 5 . 2 R

2 3 4

2 3 4 . 1

You have 15 minutes in which to measure the levels. After that, the appliance switches back from “chimney sweep” mode to normal mode.

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6 720 610 602 GB (03.02)

Maintenance

9 Maintenance

B The User should be recommended to have the appli-

ance serviced regularly by a competent person.

B Use only genuine spare parts B Refer to the Spare Parts List when ordering spare

parts.

B Always renew seals and O-rings removed during

servicing or repair work.

B Use only the following types of grease:

– Water valve: WRAS approved silicon based

grease

– Unions: approved sealant.

B To drain the appliance shut the system valves and

open the pressure relief valve.

B Upon completion of any electrical work check for

earth continuity, correct polarisation and resistance to earth.

Replace the text display module or the Heatronic PCB

If the text display module is replaced, the service function settings are retained.

B The remaining settings have to be re-entered.

If the Heatronic PCB is replaced: B Re-enter the service function settings as recorded in

the commissioning record.

B Always disconnect the appliance from

the electrical power supply (fuse, circuit breaker) before carrying out any work on the electrical systems or components.

B Always turn off the gas cock before car-

rying out any work on components which carry gas.

There is a Service booklet for the Engineer, order no. 7 181 465 347, available to competent persons.

All safety and control systems are monitored by the Bosch Heatronic. In the event of a component fault, the textdisplay shows a fault code.

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6 720 610 602 GB (03.02)

Maintenance

9.1 Pre-Service Check List

Date

1 Call up the last fault stored by the text-

display , (see page 30).

2 Check ionisation current, Service

Function 3.3, (see page 38).

3 Perform visual check of air/flue duct.

Visual check of diaphragm for soiling and splits (see page 40).

4 Check gas supply pressure

(see page 33).

mbar

5 Test combustion air/flue gas

(see page 35).

6 Check CO2 setting for min./

max. (gas/air ratio) (see page 35).

min. %

max. %

7 Check gas and water systems for

leaks (see page 15).

8 Check hot water outlet temperature

(see page 38).

9 Check heat exchanger

(see page 38).

mbar

10 Check burner (see page 39).

11 Clean condensation trap

(see page 40).

12 Check charge pressure of

expansion vessel matches static head of heating system.

mbar

13 Check central heating system

pressure.

mbar

14 Check electrical wiring for damage.

15 Check heating programmer settings in

the textdisplay.

16 Check appliances that are part of

the heating system.

Table 17

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6 720 610 602 GB (03.02)

Maintenance

9.2 Description of servicing operations

The combustion performance must be checked before and after any servicing work on the combustion and burner components. Refer to section 8.2.

Checking the ionisation current, Service Function 3.3

B Select Service Function 3.3. (See page 31 “Display-

ing Service Functions”)

If the display shows 2 or 3, the ionisation current is OK. If the display shows 0 or 1, the electrode assembly (32.1, page 6) must be cleaned or replaced.

Domestic hot water

If the flow rate is too slow: B remove the domestic hot water heat exchanger and

replace,

-or-

B descale with a descaling agent approved for use on

stainless steel.

B Before removing the heat exchanger shut the inlet

valve and drain the hot water circuit.

B Use new seals when replacing the heat exchanger.

Fig. 44

Primary Heat exchanger

There is a special accessory kit (no. 840) for cleaning the heat exchanger, order no. 7 719 001 996.

B Check control pressure on the air - gas mixer unit at

max. rated heat output using an electronic manometer.

Fig. 45

B Remove cleaning access cover (415, page 6) and

the metal plate below it, if present. Refer to fig. 2.

B Unscrew condensation trap and place suitable con-

tainer underneath. Refer to fig. 46.

B Remove the fan and the burner as described in the

text headed “Burner” (see page 39).

Fig. 46

7 181 465 330-06.1R

The heat exchanger should only be cleaned if the control pressure is

5.0 mbar (ZWBR 8-30)

4.5 mbar (ZWBR 11-37)

(depression) or less.

6 720 610 332-69.1R

6 720 610 332-72.1R

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6 720 610 602 GB (03.02)

Maintenance

B Loosen any deposits in the heat exchanger from top

to bottom using the cleaning blade. Refer to fig. 47.

Fig. 47

B Clean the heat exchanger from top to bottom using

the brush. Refer to fig. 48.

Fig. 48

B Flush the heat exchanger from the top. Refer to

fig. 49.

B Clean out the condensate collector and trap connec-

tion (with other end of brush).

Fig. 49

B Refit the clean-out cover using a new seal and

tighten screws to torque of approx. 5 Nm.

Burner

B Check that the gas cock is turned off and the master

switch is in the OFF position

B Remove the clips (1) and unscrew the two bolts (2).

Refer to fig. 50.

B Unscrew and remove the two hexagon screws secur-

ing the fan (3).

B Slacken fully the rear securing bolt (4). B Remove the burner coverplate.

Fig. 50

B Remove the burner skin and clean components. Do

not use a wire brush. Refer to fig. 51.

Fig. 51

B Re-assemble burner in reverse order using a new

seal.

B Adjust gas/air ratio. Refer to section 8.2.

6 720 610 332-73.1R

6 720 610 332-74.1R

6 720 610 332-75.2R

7 181 465 330-04.1R

7 181 465 330-08.1R

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6 720 610 602 GB (03.02)

Maintenance

Condensation trap

In order to prevent spillage of condensate the condensation trap should be completely removed, (see page 38, fig. 46).

B Unscrew condensation trap and check connection

to heat exchanger is clear.

B Remove condensation trap cover and clean. B Fill condensation trap with approx. 1/4 l of water and

refit.

Electrode assembly

B Switch off the master switch. B Pull off the leads from the electrodes. Refer to fig. 2. B Unscrew the two fixing screws and carefully remove

the electrode assembly . Refer to fig. 45.

B Clean the electrodes with a non-metallic brush. (The

spark gap should be 4,5 mm ± 0,5 mm.)

B Replace and re-connect the assembly taking care

not to mislay the inspection window.

Diaphragm in mixer unit for ZWBR 8-30 ICC2

B Open mixer unit (29). B Carefully withdraw diaphragm (443) from fan intake

tube and check for soiling and splits.

Fig. 52

B Carefully refit diaphragm (443) the correct way

round into the fan intake tube.

B Seal the mixer unit (29).

Diaphragm in mixer unit for ZWBR 11-37 ICC2

B Remove fan and mixer unit assembly.

Fig. 53

B Unscrew mixer unit (29). B Remove sleeve. B Carefully remove diaphragm (443) and check for

soiling and cracks.

B Refit diaphragm (443) taking care to ensure it is the

correct way round.

B Refit mixer unit (29) and fan assembly.

B Take care not to damage diaphragm

(443) when removing and refitting it.

443

6 720 610 790-07.2R

The flaps of the diaphragm (443) must open upwards.

443

6 720 610 910-63.1R

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Maintenance

Siphon

B Unscrew the clip and disconnect the pipe to the

siphon.

B Remove the yellow plug to drain the siphon. B Unscrew the securing nut from beneath the side

facia and remove the siphon. Refer to figure below.

B Refit and prime the siphon.

Fig. 54

Expansion vessel

The expansion vessel should be checked once a year.

B Depressurise appliance. B If necessary, adjust expansion vessel charge pres-

sure to static head of the heating system.

Heating system pressure

B The pointer on the pressure gauge should be 1 bar. B If the pointer is below 1 bar (when the system is

cold), water should be added until the pointer is 1 bar again.

B Max. pressure of 2.5 bar when the heating system

water is at maximum temperature must not be exceeded. If this pressure is exceeded then an extra expansion vessel must be fitted in the system return as close to the appliance as possible.

B If the system does not retain the pressure, the expan-

sion vessel and the heating system should be checked for leaks.

9.3 Replacement of Parts

Before changing any components check that the gas is turned off and that the appliance is electrically isolated. When necessary close the system valves and drain the appliance.

Refitting is a reverse of the procedure for removal using new seals or o-rings as appropriate.

9.3.1 PCB control board and transformer

B Switch off the appliance. B Disconnect appliance from the power supply. B Unplug all connectors from the control box (inc.

keyed plug). Access is gained by removing the covers. Refer to fig. 25, 26.

B Remove screw holding power connector earth lead

and remove earth lead.

B Remove two top fixing screws from the control box.

Refer to fig. 55.

Fig. 55

B Lower the control box. B Unscrew earth lead. B Unscrew four fixing screws from cover plate. Refer to

fig. 56.

B Prise off cover plate. B Pull off transformer. B Remove pcb holder.

Fill the system using the WRAS approved filling loop.

6 720 610 602

- 16.

Siphon

Condensate Drain

7 181 465 330-09.1R

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6 720 610 602 GB (03.02)

Maintenance

B Remove the pcb control board.

Fig. 56

Fuses

B Remove the connections covers. Refer to fig. 25,

26.

The fuses are located adjacent to the mains connector block and connector ST18. Refer to fig. 4.

Fuse, item 312, is only replaceable by removing the pcb.

Spare fuses are fixed to the connections cover. A fuse pack is available: Part number 8 744 503 010 0.

9.3.2 Fan Assembly

Fig. 57

B Switch off the appliance. B Undo lower pipe union on gas pipe (1.). Refer to

fig. 57.

B Remove fan lead and earth connector (2.). The earth

connector has a positive clip fixing.

B Remove fixing screws attaching fan to the burner

cover (3.).

B Remove fan together with gas pipe and mixer unit. B Separate the fan from the pipe and mixer unit by

twisting the mixer unit to release it (4.).

9.3.3 Pump

B Switch off the appliance. B Disconnect the appliance from the power supply. B Remove two switchbox fixing screws (1.). Refer to

fig. 58.

B Lower switchbox (2.). B Remove screw from underside of right-hand plastic

cover plate (3.).

B Pull cover plate forwards to remove (4.). B Unscrew and remove the the siphon by releasing the

jubilee clip. Refer to fig. 54.

B Unscrew the pump union nuts (5.). Refer to fig. 58. B Carefully remove the pump and disconnect the

leads.

7 181 465 330-10.1

7 181 465 330-05.1R

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6 720 610 602 GB (03.02)

Maintenance

Alternatively

B After removing the siphon release the four Allen

screws and remove and replace the pump head.

Fig. 58

9.3.4 3-way diverter valve

B Switch off the appliance. B Disconnect appliance from the power supply. B Turn off service cocks. B Unplug connector from 3-way valve motor. Refer to

fig. 59.

B Pull out retaining clip. B Remove motor. B Disconnect the relief valve drain. B Disconnect the pressure gauge by withdrawing the

clip and pulling out the capillary head.

B Undo pipe unions by withdrawing the clips.

B Remove 3-way valve.

Fig. 59

After refitting: B Fill system, bleed and re-pressurise

(see Installation Instructions).

9.3.5 3-way diverter valve motor

B Switch off the appliance. B Turn off the service cocks. B Unplug connector from 3-way valve motor. Refer to

fig. 59.

B Pull out retaining clip. B Remove motor.

9.3.6 Sensors

B Check that the appliance is electrically isolated.

Central Heating Flow Temperature Sensor – Item 36, fig. 2, 55

B Pull-off the connector. B Release the sensor clip and withdraw the sensor. B Apply heat transfer paste to the replacement sensor.

Safety Temperature Limiter – Item 6, fig. 2, 55

B Pull-off the connectors. B Unscrew the sensor.

Flue Temperature Limiter – Item 9, fig. 2, 55

B Pull-off the connectors. B Unscrew the sensor.

7 181 465 330-03.1R

7 181 465 330-12.1R

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Maintenance

Domestic Hot Water Temperature Sensor – Item 6.1, fig. 2

B Check that the inlet water valve is closed and the

domestic hot water circuit is drained.

B Release and pull-off the connector. B Unscrew the sensor.

9.3.7 Gas Valve

B Check that the gas cock is turned off. B Lower the control panel. Refer to fig. 58. B Pull off the solenoid connections at the rear of the

valve.

B Undo the union, within the inner casing, securing the

valve to the gas/air tube. Refer to fig. 57.

B Remove the white plastic cap from the gas valve. B Release the gas inlet union at the manifold assembly. B Unscrew the two screws securing the gas valve

assembly bracket to the back panel and withdraw the assembly.

B Transfer the bracket and inlet pipe assembly to the

new gas valve.

B Check for gas soundness when the new gas valve

has been fitted.

B Recheck the combustion performance as described

in section 8.1.

Fig. 60

9.3.8 Domestic Hot Water Heat Exchanger

B Refer to section 9.2. B Use new seals when fitting the new heat exchanger.

9.3.9 Electrode assembly

B Refer to section 9.2. B Use a new seal if the existing seal is damaged.

9.3.10 Pressure gauge

B Drain the appliance. B Lower the facia. Refer to fig. 58. B Twist the pressure gauge head anti-clockwise to

release it from the casing. Refer to fig. 2.

B Disconnect the capillary head from the rear of the

diverter valve by withdrawing the clip and pulling out the head. Refer to fig. 59.

9.3.11 Expansion vessel

B Drain the appliance. B Undo the union connection at the base of the vessel.

Refer to fig. 2.

B Unscrew the top and bottom fixing screws and

remove the vessel.

B Set the pressure of the new vessel to that required

by the system.

9.3.12 Pressure Relief Valve

B Drain the appliance. B Disconnect the drain pipe from the valve. Refer to

fig. 30.

B Pull-out the clip securing the valve. B Pull-out the valve. B Ensure that the replacement valve is fully entered

before fitting the clip.

9.3.13 Burner

B Refer to section 9.2.

6 720 610 602 - 04.1O

Page 45

6 720 610 602 GB (03.02)

Maintenance

9.3.14 Flow switch

B Shut the mains water inlet valve and drain the domes-

tic hot water circuit.

B Pull-off the connectors from the micro-switch. B Unscrew the inlet and union connection and remove

the assembly.

B Reset the domestic hot water flow rate on the new

assembly.

Fig. 61

9.3.15 Primary Heat Exchanger

B Drain the appliance. B Check that the gas supply is turned off. B Check that the appliance is electrically isolated. B Remove the fan assembly complete with the gas/air

tube and mixer assembly. Refer to section 9.3.2.

B Remove the burner. Refer to section 9.2. B Disconnect the sensors. Refer to section 9.3.6. B Undo the central heating flow union. B Undo the top connection of the pump. Refer to

fig. 57.

B Undo the grey plastic cap, next to the top pump con-

nection at the base of the heat exchanger.

B Unscrew and remove the condensate trap. Refer to

section 9.2.

B Unscrew and remove the two screws securing the

heat exchanger top bracket to the rear panel.

B Lift up the flue duct, item 271, refer to fig. 2. B Pull forward from the top and lift the heat exchanger

from the casing.

B Transfer components, as necessary, to the new heat

exchanger.

B Ensure that all the seals are in place and all of the

connections are tight before re-commissioning the appliance.

Fig. 62

6 720 610 602 - 05.10

INLET

OUTLET

6 720 610 602 - 06.10

Page 46

6 720 610 602 GB (03.02)

Appendix

10 Appendix

10.1 Fault Codes

More detailed fault finding procedures are described in the Service Booklet for the Engineer number 7 181 465 347.

Display code

Description Remedy

A1 pump has run dry Check system pressure, add water and bleed

system as necessary

A7 Hot water NTC sensor defective. Check hot water NTC sensor and connecting

lead for circuit breaks/short circuits.

A8 Break in communication Check connecting lead to TR2 b1 Keyed plug not detected. Insert keyed plug correctly, test and replace if

necessary.

C1 Fan speed too low. Check fan lead and connector, and fan; replace

as necessary.

d3 Jumper 8-9 not detected. Connector not connected, link missing, under-

floor heating limiter tripped.

E2 CH flow NTC sensor defective Check CH flow NTC sensor and connecting

lead.

E9 Safety temp. limiter in CH flow has tripped. Check system pressure, check safety temp. lim-

iters, check pump operation, check fuse on pcb, bleed appliance.

EA Flame not detected. Is gas cock turned on? Check gas supply pres-

sure, power supply, igniter electrode and lead, ionisation sensing electrode and lead, flue duct and CO2 level.

F0 Internal error. Check electrical connector contacts, program-

mer interface module ignition leads and bus module are not loose; replace pcb or bus module if necessary.

F7 Flame detected even though appliance

switched off.

Check electrode assembly, dry pcb. Flue clear?

FA Flame detected after gas shut off. Check gas valve and wiring to gas valve. Clean

condensation trap and check electrode assembly. Flue clear?

FC Textdisplay not detected. Check connecting lead between Textdsiplay

and Heatronic , replace Textdisplay if necessary

Fd Reset button pressed by mistake. Press reset button again P1, P2,

P3, P1...

Please wait, initialisation in progress. 24 V fuse blown. Replace fuse.

Table 18

Page 47

6 720 610 602 GB (03.02)

Appendix

10.2 Short parts list

Key Description Qty GC Spare part number

1 Sensor - Flue gas temp. 1 8 729 000 144 0 2 Sensor - CH flow temp. 1 8 714 500 087 0 3 Sensor - DHW flow temp. 1 8 714 500 054 0 4 Control board pcb 1 8 748 300 418 0 5 Gas valve ZWBR 8-30 1 8 747 003 516 0

5.1 Gas valve ZWBR 11-37 1 8 747 003 515 0 6 Fan assembly 1 8 717 204 325 0 7 Fan washer 1 8 729 000 183 0 8 Expansion vessel 1 8 715 407 246 0 9 Relief valve 1 8 717 401 012 0 10 Electrode assembly 1 8 718 107 077 0 11 Electrode lead 1 8 714 401 999 0 12 Pump 1 8 717 204 477 0 13 Pressure gauge 1 8 717 208 079 0 14 Burner skin seal 1 8 711 004 168 0 15 Transformer - facia 1 8 747 201 358 0 16 Flow switch 1 8 717 002 110 0 17 3-way diverter valve 1 8 717 010 062 0 18 Heat exchanger washer 1 8 710 103 153 0 19 Washer set Condensation

Trap

1 8 710 103 154 0

20 Fuse set 1 8 744 503 010 0 21 Service set Water Valve 1 8 710 503 031 0 22 Domestic Hot Water Heat

Exchanger

1 8 715 406 659 0

23 Text Display 1 8 747 208 103 0 24 Primary heat exchanger 1 8 715 406 615 0 25 Diaphragm 1 8 715 505 801 0

Table 19

Page 48

6 720 610 602 GB (03.02)

Appendix

10.3 Heating/hot water output settings ZWBR 8-30 N.G.

10.4 Heating/hot water output settings ZWBR 11-30 L.P.G

10.5 Heating/hot water output settings ZWBR 11-37 N.G.

10.6 Heating/hot water output settings ZWBR 14-37 L.P.G

Natural gas G20

Display code

Heat output, kW

Heat input, kW

Gas vol. flow rate (l/min at t

V/tR

= 80/60 C)

30 9.1 9.2 16.0

40 12.1 12.2 21.4

50 15.1 15.3 26.7

60 18.1 18.3 32.0

70 21.1 21.4 37.4

80 24.2 24.4 42.7

90 27.2 27.5 48.0

100 30.2 30.5 53.4

Table 20

Propane

Display code

Heat output kW Heat input kW

40 12.1 12.2

50 15.1 15.3

60 18.1 18.3

70 21.1 21.4

80 24.2 24.4

90 27.2 27.5

100 30.2 30.5

Table 21

Natural gas G20

Display code

Heat output, kW

Heat input, kW

Gas vol. flow rate (l/min at t

V/tR

80/60˚C)

30 11.1 11.3 19.7

40 14.9 15.0 26.3

50 18.6 18.8 32.8

60 22.3 22.5 39.4

70 26.0 26.3 45.9

80 29.7 30.0 52.5

90 33.4 33.8 59.1

100 37.1 37.5 65.6

Table 22

Propane

Display code

Heat output, kW Heat input, kW

40 14.9 15.0

50 18.6 18.8

60 22.3 22.5

70 26.0 26.3

80 29.7 30.0

90 33.4 33.8

100 37.1 37.5

Table 23

Page 49

6 720 610 602 GB (03.02)

Appendix

10.7 Operational Flow diagrams

10.7.1 Domestic hot water function

Fig. 63

Mains

switch

ON.

Green

light

ON.

Burner lights.

Red light ON.

Ignition spark for

5 seconds.

Fan runs to purge

gas from burner.

Repeats 5 times

before lock-out.

Hot

water

demand.

Pump ON

Diverter valve

operates.

Heat input

modulates to

maintain the

delivery

temperature.

Gas valve

closes.

Red light

OFF.

Fan runs for

upto 3 mins.

Pump runs

for 30secs.

Over temperature

shut-down if water

temperature is 8°C

above set value.

Burner remains OFF

until flow temperature

is below set value.

Gas valve shuts.

Pump remains ON.

Demand

ends.

Yes

** NOTE:

The appliance controls can be set to one of

2 modes of operation.

“

Comfort

“ mode -

Full pre-heat

“

ECO

“ mode -

a) Operates as an instantaneous combination

boiler.

b) Demand Detection: a short demand (less

than 5 seconds) switches the control to

“Comfort“ mode for 5 mins. Mini pre-heat.

The Factory setting is “

Comfort

“ mode.

Fan to

start speed.

Gas valve opens.

Pre-heat

mode.**

Ignition sequence

Pre-heat

mode.**

Burner shut-down if

primary temperature

exceeds 94 °C remains

OFF until 78 °C

Pump ON

Diverter valve

operates.

Fan to

start speed.

Gas valve opens.

Pre-heat satisfied.

Ignition sequence

Burner lights.

Red light ON.

Ignition

spark

5 secs

6 720 610 576 - 24.1O

Page 50

6 720 610 602 GB (03.02)

Appendix

10.7.2 Central heating function

Fig. 64

Mains

switch

ON.

Fan min.

speed for

90 secs.

Green

light

ON.

Burner lights.

Red light ON.

Ignition spark for

5 seconds.

Fan runs to purge

gas from burner.

Repeats 5 times

before lock-out.

Room thermostat

and/or mains

programmer or

link ON

AND

Electronic facia

programmer

(if fitted) ON

AND

CH control knob

ON.

demand.

Pump ON

Fan to

start speed.

Gas valve opens.

Burner

stabilises at

start speed

for 5-10 secs

Fan speed

reduces

over 15

secs.

Gas valve

closes.

Red light

OFF.

Minimum

heat input

for 15min.

Boiler

operates to

match

system load

and CH

control

setting.

Boiler

unused for

long

period.*

Over temperature

shut-down if water

temperature is 5°C

above set value.

Burner remains OFF

until flow temperature

is below set value.

Gas valve shuts.

Pump remains ON.

Pump and Fan

run for upto

3 mins.

CH demand

satisfied.

Yes

* NOTE: The sequence ensures that the condensate siphon is not empty

after long

OFF

periods. (More than 24 hours without a demand).

Ignition sequence

6 720 610 576 - 25.1O

Page 51

6 720 610 602 GB (03.02)

Appendix

Page 52

AppendixAppendix

EXCELLENCE COMES AS STANDARD

Manufactured exclusively for British Gas by The Bosch Group

Bosch Group, Worcester Heat Systems, Cotswold Way, Warndon, Worcester WR4 9SW.

Telephone: (01905) 754624 Fax: (01905) 754619

Page 53

Service Booklet for the Engineer for Gas Condensing Boilers

6 720 610 333-00.1

ZSBR 7-28 ICS1 GC-Number: 41 108 04 ZWBR 8-30 ICC2 GC-Number: 41 108 09 ZBR 8-35 ICS1 GC-Number: 41 108 05 ZWBR 11-37 ICC1 GC-Number: 41 108 10

ZWBR 7-28 HE plus GC-Number: 47 311 56 ZWBR 11-35 HE plus GC-Number: 47 311 57

7 181 465 347 (01.07) OSW

Page 54

7 181 465 347 (01.07)2

Contents

Safety precautions 3

Symbols 3

1 Layout of Appliance (ZSBR/ZWBR) 4

2 Operation 5

2.1 Standard display 5

2.2 Displaying service functions 5

2.3 Setting service functions 5

2.4 Resetting service functions to factory settings 5

2.4.1 Resetting service functions 0.0 to 4.9 to their factory settings (Reset 1): 5

2.4.2 Resetting service functions 0.0 to 9.9 to the factory setting (Reset 2): 5

3 Boiler service functions 6

3.1 Summary 6

3.2 Explanation of service functions 9

4 Rectifying faults 14

4.1 Boiler failure codes indication 14

4.1.1 ... on the boiler 14

4.1.2 ... on the programmer (optional accessory) 14

4.2 Summary 14

4.2.1 Appliance faults 14

4.2.2 Faults that are not indicated on any display 14

4.3 How to use the fault tables 16

4.4 Faults indicated on display 17

4.5 Faults that are not displayed 36

4.5.1 Appliance faults 36

4.5.2 Programmer faults 41

5 Appendix 45

5.1 NTC values 45

5.1.1 Outside temperature sensor 45

5.1.2 CH flow NTC sensor, heat store NTC sensor, constant hot water NTC sensor and hot water NTC sensor 45

5.2 Electronic schemes 46

5.3 List of most important replacement parts 47

5.4 Approved corrosion inhibitors and anti-freeze fluids for central heating water 48

5.5 Detecting corrosion by CFCs 49

Page 55

7 181 465 347 (01.07)

Safety precautions

Repairs

B Repairs may only be carried out by an approved

installer!

B Before carrying out any work on the appliance,

switch it off at the master switch!

B Even when the appliance is switched off at the mas-

ter switch, some components on the PCB control board inside the control box are still live. Therefore:

B Before carrying out any work on the electrical parts

of the appliance fully disconnect it from the power supply (e. g. by means of fuse or circuit breaker)!

B Flue ducting must not be modified in any way. B Use only original spare parts!

Instructions to the customer

B Advise the customer that he/she must not make any

modifications to the appliance or carry out any repairs on it.

B Draw attention to the need for an annual service (or

maintenance contract if applicable).

Symbols

Signal words indicate the seriousness of the hazard in terms of the consequences of not following the safety instructions.

• Caution indicates that minor damage to property

could result.

• Warning indicates that minor personal injury or seri-

ous damage to property could result.

• Danger indicates that serious personal injury could

result. In particularly serious cases, lives could be at risk.

Notes contain important information in cases where there is no risk of personal injury or damage to property.

Safety instructions in this document are identified by a warning-triangle symbol and are printed on a grey background.

Notes are identified by the symbol shown on the left. They are bordered by horizontal lines above and below the text

Page 56

7 181 465 347 (01.07)4

Layout of Appliance (ZSBR/ZWBR)

1 Layout of Appliance (ZSBR/ZWBR)

Fan fixing screws

Burner fixing screws

Electrode assembly: Flame sensing electrode Ignition electrodes

CH flow NTC sensor

CH flow safety temperature limiter

Variable-characteristic pump

Automatic vent

as flow

restrictor: adju-

ting screw for

O2 max.

Gas valve: adjusting screw for CO

min.

Plate-type heat exchanger (ZWBR)

Hot water NTC sensor (ZWBR)

CH flow

Silencer

Fan

Fan connector

Mixer unit

Condensation trap

Gas supply pipe

Flue gas safety temperature limiter

Testing points: flue gas air

Inspection opening

Water switch (ZSBR)

Change-over valve motor

Change-over

valve

Heatronic

Transformer

Page 57

7 181 465 347 (01.07)

Operation

2 Operation

Instructions on the use of the text display module are given in the operating and installation instructions for the boiler.

Fig. 1 Controls

a Display b “Up” or “More” button c “Down”, or “Less” button d “Back” button e “Nest” button f “Delete” button

2.1 Standard display

The text display shows the time, the CH flow temperature and the measured outside temperature in plain English.

In addition, the 2-digit display also shows the current CH flow temperature in Heating mode and Hot Water mode (display range 00 °C to 99 °C).

2.2 Displaying service functions

B Press any button to activate the main menu. B Press or button until the arrow cursor is

pointing to Settings.

B Press the button. B Press or button until the arrow cursor is

pointing to Service .

B Press the button. B Press button to select Display service

parameters. Service function 0.0, Last fault is displayed.

B Press or button to cycle through the

current settings.

B Press button to exit the menu.

2.3 Setting service functions

B Press any button to activate the main menu. B Taste or button until the arrow cursor is

pointing to Settings.

B Press the button. B Press or button until the arrow cursor is

pointing to Service.

B Press the button.

The cursor is pointing to Display service parameters.

B Press and hold the button (for about 5 sec-

onds) until the display shows shows Adjust service parameters and the first service function to be set, e.g. 2.0, Operating mode. If a fault has occur red, the display will show 0.0 and the last fault.

B Press or button until the desired service

function is displayed.

B Press the button.

The first line of the display shows Change value.

B Use the and buttons to enter the

required setting.

B Press the button.

The text display shows ATTENTION Store set- tings?.

B Press or to select yes or no. B Press to confirm your selection.

The text display shows Please wait ..., and the service function is then displayed with the new setting.

B Press the or button until the next func-

tion you wish to change is displayed.

-or-

B Press the button to exit the menu.

2.4 Resetting service functions to factory settings

2.4.1 Resetting service functions 0.0 to 4.9 to their factory settings (Reset 1):

B Power OFF the appliance. B Press the button and keep it pressed. B Switch on the appliance, press and hold the but-

ton until the display shows r1 followed by [ ] .

2.4.2 Resetting service functions 0.0 to 9.9 to the factory setting (Reset 2):

B Power OFF the appliance. B Simultaneously press and hold buttons and . B Switch on appliance, press and hold the and

buttons until the display shows r2 followed by [ ] .

6 720 610 337-08.1R

To reset all parameters (except service settings) set on the text display module):

B Press and hold the button until the

settings are deleted.

Page 58

7 181 465 347 (01.07)6

Boiler service functions

3 Boiler service functions

3.1 Summary

Text display message Display

Range adjustable from - to

Reset Value

0.0 Last fault 00 - FF Clear only 0

0.1 Flow temp. sensor 0 - 99 °C - -

0.2 Hot water temp. sensor 0 - 99 °C - -

0.3 Stor. tank temp. sensor1 0 - 99 °C - -

0.4 Stor. tank temp. sensor2 0 - 99 °C - -

1.2 Code plug 8714411 XXX 0 - 255 - -

1.5 Required flow temp. 0 - 99 °C - -

1.9 Module detection no module detected

bus module

2.0 Operating mode - normal Min Max

normal

2.2 Pump switch mode - 1 - 3 2

2.3 Stor. tank charge output - 0 - 100% 100 %

2.4 Anti-cycle mode - 0 - 15 min 3 min

2.5 Max. flow temperature - 35 - 88 °C 88 °C

2.6 Switch.diff.flow temperature - 0 - 30 °C 0 °C

2.7 Autom. anti-cycle mode - on

off

2.9 Actual output 0 - 100 % - -

3.0 Fan speed 0 - 255 U/s - -

3.3 Ionisations current no

low middle high

3.4 Pump mode - 0 - 3 0

3.5 Pump blocking time - 0 - 240 s in 15-s increments

0 s

3.6 Software version BF 11.XX - -

Table 1

Page 59

7 181 465 347 (01.07)

Boiler service functions

3.9 Link 8 - 9 open closed

Link Ls-Lr open

closed

4.0 Stor. tank. therm.. (7-9) blocked heat demand

4.1 Room therm. LSM blocked heat demand

LSM release blocked

heat demand

4.2 Timer ch. 1 (heating) blocked heat demand

Timer ch. 2 (hot wat.) blocked

heat demand

4.4 Heat demand (heating). yes no

Heat demand (stor. tank). yes

4.5 Heat demand (hot water). yes no

Keep hot period yes

4.6 Internal regulator blocked heat demand

5.0 Max. output (heating) - 27 - 100% 100 %

5.1 Permanent ignition - no

yes

5.2 GFA status / error 00h - FFh - -

5.5 Min. output - 27 - 100 % 27 %

5.8 Cyclic boiler starts - on

off

5.9 Fan speed (start) - low

high

low

6.7 Pump off (hot water). - off

off

Text display message Display

Range adjustable from - to

Reset Value

Table 1

Page 60

7 181 465 347 (01.07)8

Boiler service functions

6.8 Cycle time (hot water) - 0 - 60 min 0 min

6.9 Duration (hot water) - 0 - 30 min 1 min

7.0 Pump map (heating) - 0 Pump step adjustable

1 Const. pressure high 2 Const. pressure middle 3 Const. pressure low 4 Prop.pressure high 5 Prop.pressure low

4 Prop. pressure high

7.1 Map pump step (heat.). - 2 - 7 7

7.2 Antiblock. map pump. - off

7.3 Air purge mode - off on autom. deaktivat. permanent on

on autom. deaktiv at./ off

7.4 Actual map pump step 1 - 8 - -

7.5 Map pump load index 0 ... 255 - -

7.6 Map pump type 0 .. 99 - -

7.7 Output reduction - off

only in heating mode only in hot water mode in heat./hot water mode.

only in heating mode

8.5 Siphonfillprogram - on, boiler min.output, on, adjust. min output, off

on, boiler min. output

9.2 Hot water on demand - off on

9.3 GFA-Asic-error 00h - FFh - -

1) The reset value depends on the code plug.

Text display message Display

Range adjustable from - to

Reset Value

Table 1

Page 61

7 181 465 347 (01.07)

Boiler service functions

3.2 Explanation of service functions

0.0 Last fault

The last fault can also be recalled for servicing purposes when the appliance is functioning correctly.

To delete the stored fault:

B Delete fault (no fault displayed). B Press the button. B Use the or button to select yes. B Press the button.

If a list of the last 10 indicated faults is required for servicing purposes, look under Settings -> Service -> Fur- ther options -> Fault history.

0.1 Flow NTC

The temperature measured by the NTC sensor on the CH flow pipe is indicated.

0.2 Hot water NTC

The temperature measured by the NTC sensor on the plate-type heat exchanger outflow is indicated.

0.3 Storage tank NTC 1

Indirectly heated heat store (SO..., SK..., ST...): The temperature measured by NTC sensor 1 in the heat store is indicated.

Stratified-charge tank (ST...S): The temperature measured by NTC sensor 2 at the bot- tom of the heat store is indicated.

0.4 Storage tank NTC 2

Stratified-charge tank (ST...S): The temperature measured by NTC sensor 2 at the top of the heat store is indicated.

1.2 Code plug

The 10-digit part number of the code plug is indicated. The code plug determines the appliance functions. If

the appliance is converted from natural gas to LPG or vice versa (using conversion kit) the code plug also has to be changed.

1.5 Desired flow temp.

The CH flow temperature demanded by the text display module or a programmer connected to the bus module is displayed.

1.9 Module detection

The text display module shows the modules detected by the appliance.

2.0 Operating mode

There are 3 operating modes to choose from.

• Normal mode: the appliance operates according to

the commands received from the programmer.

• Min mode: the appliance runs constantly at minimum

output. The text display shows MIn mode. The 2-digit display alternates between the CH flow temperature and

– –

• Max mode: the appliance runs constantly at maxi-

mum output. The text display shows Max mode. The 2-digit display alternates between the CH flow temperature and

– –

2.3 Stor. tank charge outp

The heat store charging output can be set to any level between the minimum and maximum rated heat output for hot water according to the heat transfer capacity of the heat store.

B Enter the heat store charging output setting on the

commissioning record enclosed with the appliance.

2.4 Anti-cycle mode

This function is only active if service function 2.7 Automatic anti-cycle mode is disabled.

The anti-cycle time is factory set to 3 minutes. The shortest possible period is 1 minute (recom-

mended for single-pipe and hot-air heating systems). The setting 0 means that the anti-cycle time is disabled.

B Enter the anti-cycle time on the commissioning

record enclosed with the appliance.

2.5 Max. flow temperature

The maximum CH flow temperature can be set to between 35 °C and 88 °C (factory setting).

2.6 Switch diff. flow NTC

The switching difference is the permissible deviation from the spec ified CH fl ow temperatur e. It can be set in increments of 1 K. The adjustment range is from 0 to 30 K (factory setting: 0 K). The minimum CH flow temperature is 30 °C.

B Disable anti-cycle time (setting 0). B The switching difference setting should be entered

on the commissioning record supplied with the appliance.

If an outside-temperature controlled heating programmer is used, no setting is required. The anti-cycle time is optimised by the programmer.

If an outside-temperature controlled heating programmer is used, no setting is required on the appliance.

Page 62

7 181 465 347 (01.07)10

Boiler service functions

2.7 Autom. anti-cycle mode

If an outside-temperature controlled programmer is connected to the appliance, the anti-cycle time is adjusted automatically.

Automatic adjustment of the anti-cycle time can be disabled. This may be necessary in the case of unfavourably dimensioned heating systems.

If automatic adjustment of the anti-cycle time is disabled, the length of the anti -cycle time mus t be set under service function 2.4.

B If automatic adjustment of the anti-cycle time has

been disabled, this should be entered on the commissioning record enclosed with the appliance.

2.9 Actual output

The actual output of the appliance at the time viewed is displayed.

3.0 Fan speed

The current fan speed is displayed.

3.3 Ionisation current

The burner flame is monitored by measuring the ionisation current generated during combustion. If no ionisation current is detected, the gas valve shuts off. This ensures that unburned gas does not escape.

3.4 Pump mode (ZBR.. models only)

The possible settings are:

• Pump mode 1: if a heating pump and a 3-way valve

for charging the heat store are connected. The 3-way valve is de-energised when the heat store circuit is open.

• Pump mode 2 (factory setting): if a circulation

pump and a heat store charging pump are connected. In ECO mode, if the circulation pump and the heat store charging pump call for heat simultaneously, the system alternates between 12 minutes heating and 12 minutes hot water.

• Pump mode 3: if a circulation pump and a heat store

charging pump are connected. In ECO mode, if the circulation pump and the heat store charging pump call for heat at the same time, both pumps run simultaneously. The heat store charging temperature has priority (up to 85 °C). The hydraulic configuration must be matched to this pump mode (use of a mixer unit and hydraulic balancing).

B The pump mode setting should be entered on the

commissioning record enclosed with the appliance.

3.5 Pump blocking time (ZBR.. models only)

If the system incorporates a 3-way valve external to the appliance, the heating pump is disabled while the 3-way valve is being actuated. therefore, the blocking time of the heating pump should be ≥ the ac t uation time of th e 3-way valve. The blocking time has an adjustment range of 0 to 16, with each increment equivalent to 15 seconds. The adjustment range therefore equates to 0 to 240 seconds.

Factory setting is 30 seconds.

B Enter the pump blocking time on the commissioning

record enclosed with the appliance.

3.6 Software version

The version number of the software is displayed.

3.9 Jumper 8 - 9 /

3.9 Jumper Ls - Lr

When supplied, the appliance has a jumper fitted across terminals 8-9 (= Heat demand). If that connection is opened (e.g. by a limiter for an underfloor heating system), heating mode is disabled.

When supplied, the appliance has a jumper fitted across terminals Ls-Lr (= Heat demand). If that connection is opened (e.g. by an external 2-point programmer), heating mode is disabled.

4.0 Stor. tank therm. (7 - 9)

When supplied, the appliance has no jumper across terminals 7- 9 (= Disabled). If that connection is closed (e.g. by a heat store thermostat) heat store charging is enabled.

4.1 Room therm. LSM/ 4.1 LSM release

When supplied, a jumper is fitted across terminals LZ L1 on the LSM (= Heat demand). If that connection is opened (e.g. by a connected room thermostat), heating mode is disabled.

LSM release shows the total number of all possible enable signals connected via the LSM. As soon as a module connected to it (e.g. mechanical limiter for underfloor heating, limit switch on flue flap, combustion air flap, etc.) shuts off, heating and hot water modes are disabled.

4.2 Timer ch. 1 (heating)/ 4.2 Timer ch. 2 (hot water)

Shows the status of channel 1 of the timer integrated in the text display module or the separate programmer. If that channel’s status is “Heat demand”, heating mode will be activated according to the programmer commands.

Only applies if service function 3.4, Pump mode, is set to Pump mode 1 (external 3way valve for heat store charging is connected). Otherwise has no function.

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Shows the status of channel 2 of the timer integrated in the text display module or the separate programmer. If that channel’s status is “Heat demand”, hot water mode will be activated according to the programmer commands.

4.4 Heat demand (heating)/ Heat demand (stor. tank) (ZSBR.. only)

Heat demand (heating) shows the heat demand status for the central heating system.

If this channel’s status is “Heat demand”, heating mode will be activated according to the programmer commands.

Heat demand (stor. tank) shows the heat demand status for charging the heat store.

If this channel’s status is “Heat demand”, the heat store will be charged according to the commands from the heat store thermostat or NTC sensor.

4.5 Heat demand (hot water)/

Keep hot period (ZWBR... models only)

Heat demand (hot water) shows the heat demand status for the hot water function. If this channel’s status is “Heat demand”, the hot water function operates according to the commands from the hot water NTC sensor.

Keep hot period shows the constant hot water circuit status of the heat exchanger (ECO or Comfort mode). If this channel’s status is “Heat demand”, Comfort mode is active. If the status is “Disabled”, ECO mode with demand detection is active.

4.6 Internal regulator

The boiler has an internal anti-cycle function which prevents the burner overheating if the heat output can not be dissipated even in Min mode. The appliance will then switch off even when the system is calling for heat.

It will subsequently switch on again

• after 5 seconds in hot water mode

• after 30 seconds in heat store charging mode

• after 0 to 15 minutes in heating mode (depending on

the setting for service function 2.4 Anti-cycle mode).

The anti-cycle function is cancelled by

• switching the appliance off and on again at the mas-

ter switch,

• another demand for heat,

• activating Min or Max mode

• or briefly switching to summer mode on the tempera-

ture control for CH flow.

5.0 Max. output (heating)

Some gas suppliers demand an output-dependent basic charge.

The heating output can be limited to any level between the min. rated heat output and the max. rated heat output to suit the specific heat requirements.

The factory setting is maximum rated output – display shows “100 %”.

5.1 Permanent ignition

This function allows permanent ignition without gas supply to be activated for the purposes of checking the ignition mechanism.

5.2 GFA status/error

The status of the automatic ignition module integrated in the PCB control board is indicated.

5.5 Min. output

The min. heat input is factory set, see technical data. The modulation range can be extended at the top end to suit the chimney conditions.

B Refer to settings table for heating and heat store

charging output for details of the min. heat output in kW and the corresponding percentage (see installation instructions for boiler).

B Enter perc entage on text dis p lay modul e and confirm . B Measure gas flow rate and compare with the figures

quoted for the percentage shown. If different, correct the percentage figure!

B Enter min. rated heat output on the commissioning

record enclosed with the appliance.

5.8 Cyclic boiler starts (ZSBR 3/5-16 A... only)

When supplied, this function is activated on the above appliances and prevents start-up problems caused by poor ignition characteristics.

A truncated start cycle is activated if the burner has not been in operation for more than 3 hours.

During a truncated start cycle, the fan runs and the gas valve is opened long enough to completely fill the gas pipe with gas (approx. 1 - 2 seconds) but the burner is not ignited.

This function is not required, and can not be activated, on any other models.

6.7 Pump off (hot water)

The appliance is supplied with this function activated, i.e. there is a delay before the pump switches on in hot water mode. This means that cold water comes out of the pipe to begin with, followed by hot water once the pump switches on.

If the pump is set to switch on immediately (Pump off function deactivated), the hot water temperature rises gradually until the set temperature is reached.

Even if the heating output is limited, the full rated heat output remains available for hot water or heat store charging.

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If a stratified-charge tank is connected, it is useful to have the function activated.

The delayed cut-in of the pump then prevents cold water being pumped through the tank and cooling it down.

6.8 Cycle time (hot water) (ZWBR... only)

The appliance is supplied with the hot water cycle time set to 3 minutes.

The hot water cycle time specifies how long after hot water is drawn the pump continues to pump water through the internal hot water system.

6.9 Duration (hot water) (ZWBR... only)

The appliance is supplied with the hot water duration set to 3 minutes.

The hot water duration specifies how long after hot water is drawn heating mode remains disabled.

7.0 Pump map (heating) (not ZBR...)

The appliance is supplied with this function set to “4 Prop. pressure high”(see pump characteristic in boiler installation instructions).

The pump map indicates how the pump is controlled in heating mode. The pump switches between the various pump speeds so as to reproduce the characteristic curve selected. (The current setting can be viewed by means of service function 7.4.)

Changing the pump characteristic can be helpful if a lower pressure difference will guarantee the necessary circulation on the basis of the system dimensions and pump characteristic (see installation instructions).

If this parameter is set to “0 Pump step adjustable”, then the pump speed set under function 7.1 is active.

7.1 Map pump step (heat.) (not ZBR...)

The appliance is supplied with this function set to 1 (see pump characteristic in boiler installation instructions). However, th e setting is only active if function 7.0, Pump map (heating), is set to “0 Pump step adjustable”.

This service function corresponds to the pump speed switch used on conventional heating pumps.

7.2 Antiblock. map pump (not ZBR...)

The appliance is supplied with this function activated. If the pump threatens to jam, an oscillating pump action

is activated. Afterwards, the required ope rating mode is continued.

7.3 Aeration mode (not ZBR...)

The first time the appliance is switched on, a once-only venting function is activated. The heating pump then switches on and off at intervals. This sequence lasts about 8 minutes and the text display shows “Aeration mode”. The 2-digit display shows “

” in alternation with the CH flow temperature. The automatic vent must be opened and then closed again once the venting sequence is complete.

• If the venting function is set to “On, autom. deacti-

vat.”, once the sequence has been completed.

7.4 Actual map pump step (not ZBR...)

The currently active pump speed is displayed (see function 7.0).

7.5 Map pump load index (not ZBR...)

The load index is displayed.

7.6 Map pump type (not ZBR...)

The pump type code of the pump fitted is displayed.

7.7 Output reduction

The appliance is supplied with this function activated. It prevents overload of the heat exchanger with high CH flow temperatures.

The output of the burner is reduced according to the CH flow temperature, i.e. up to 80 °C flow temperature, full burner output is permitted. Above 80 °C, the burner output is reduced as flow temperature increases up to 90 °C at which only minimum output is available (even with maximum heat demand).

This function can be deactivated for hot water and/or central heating mode.

In order to save as much energy as possible and to mi n i m i se the po s s i b i l ity of wa t e r circulation noise, a low characteristic should be chosen.

The venting function can be activated manually after servicing.

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8.5 Siphon fill program

The trap filling programme ensures that the condensation trap is filled when the appliance is first installed or after it has been shut down for a long period: The condensation trap prevents flue gas escaping from the appliance into the room in which it is installed.

The trap filling programme is activated:

• the appliance is switched on at the master switch

• the burner has not been in operation for at least 48 hours

• the appliance is switched from summer to winter mode.

The next time the heating or hot water system calls for heat, the appliance is held at minimum output for 15 minutes. The trap filling programme remains active until the a p p l i a n c e has complet e d 15 mi n u t e s of op e r a tion at minimum output. The text display shows “Siphon fill program” and the 2-digit display alternates between „-II-“ and the CH flow temperature.

The factory setting is „1“ (activated).

9.2 Hot water on demand

The appliance is supplied with this function activated. This function relates to mode, the button lights up. The demand detection function enables maximum gas

and water economy. Briefly turning a hot water tap on and then off again signals demand to the appliance which then heats up the water to the set temperature. Hot water is then available at short notice.

9.3 GFA-Asic error (automatic ignition module,

extended messages)

The status of, or an error message from the automatic ignition module integrated in the PCB control board is displayed.

Warning: if the condensation trap is not filled, flue gas can escape!

B Only deactivate the trap filling program-

me in order to carry out servicing work.

B Always re-activate trap filling program-

me once servicing is complete.

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4 Rectifying faults

4.1 Boiler failure codes indication

4.1.1 ... on the boiler

In order to identify the specific boiler failure a two digit alphanumeric code is used. This allows a quick fault identification and solution.

The text display shows the message Fault EA. Please call service, for example. At the same time, the fault code appears on the 2-digit display, in this example: EA.

You can view an explanatory description of the fault indicated by going to Settings -> Service -> Service

parameters, in this example: EA: During operation: Flame not detected.

The failures can be divided into four basic typologies, as described:

• The appliance continues to work at a minimum function level (e. g. with error codes A5, A7, A8, AC, Ad, CC, FC).

• The appliance is locked until the failure is repaired (e. g. with error codes (b1, C1, d1, d3, E2, F0)).

• The appliance is locked, until the ON/OFF switch is turned (A1).

• The boiler has shut down and locked out ( flashes) and remains so until the cause of the fault has been eliminated and the lock-out cancelled (e.g. E9, EA, F0, F7, FA,Fd).

4.1.2 ... on the programmer (optional accessory)

A TW 2 remote control unit can also be connected to the text display module.

If other/more functions are required, another programmer must be connected. Those programmers are then controlled via the bus module BM1.

For more detailed information, refer to the installation instructions for the boiler and the installed programmer.

Faults on this programmer are indicated by text messages on the programmer display.

Once the fault has been put right, the programmer reverts to its normal display.

4.2 Summary

4.2.1 Appliance faults

4.2.2 Faults that are not indicated on any display

To unblock the appliance:

B Press the unblock button until the

digit –– appears on the display. Once the appliance starts up successfully, the fault disappears from the text display.

Appliance faults

ZBR ... A

ZSBR ... A

ZWBR ...A

Page

A1 X X 17

A5 X 18

A7 XXX 19

A8 XXX 20

Ad XXX 21

b1 XXX 22

C1 XXX 23

d3 XXX 24

E2 XXX 25

E9 XXX 26

EA XXX 28

F0 XXX 32

F7 XXX 33

FA XXX 34

FC XXX 35

Fd XXX 35

Table 2

Appliance faults

ZBR ... A

ZSBR ... A

ZWBR ...A

Page

Excessive burner noise, rumbling noises

XXX 36

Flue gas levels incorrect, CO level too high

XXX 37

Ignition too harsh, ignition poor

XXX 38

Boiler indicates P1, P2, P3 at start-up and then restarts with P1, ...

XXX 36

Table 3

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Loose or broken contact on heat store NTC sensor

XX 39

Specified CH flow temperature from TA... programmer exceeded

XX 40

Programmer faults

TR 2

Page

Set room temperature not reached

X41

Set room temperature exceeded by large amount

X43

Set room temperature not reached

Temperature rises instead of falling

X43

Room temperature too high in Economy mode

X43

Incorrect or no modulation X 43

Heat store fails to heat up 44

Table 4

Appliance faults

ZBR ... A

ZSBR ... A

ZWBR ...A

Page

Table 3

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4.3 How to use the fault tables

The procedure is explained using the fault code EA as an example:

The table heading shows the fault code and a general description of the fault.

In the example shown, you are instructed to note the current settings before going any further. If you can see the flame (answer to question is “yes”) you move on to Step 5. (↓ 5.). The question asked in Step 5 is “Is there a problem with the flue”. The flue must then be checked.

If the answer to the first question (“Is burner flame visible?”) was“no””, then you go to and answer Question 2, “Is the gas cock turned on?”. If the gas cock is turned off, it must be turned on and the appliance reset. To do so, you press the button. Restart th e ap p l i a nce and run through a complete heat-demand cycle until the appliance switches off.

If the fault is now cured, the appliance will revert to normal operation and the fault-finding process is complete. Now simply re-check the setting of the two temperature controls.

If the fault EA recurs during the heat-demand cycle, it will be shown on the display again. In that case continue the fault finding procedure from Step 3 (thermal cut-out in gas cock) as described above.

If a different fault code is displayed after the heatdemand cycle, find the appropriate section of the fault finding table and work through the procedure described step by step.

EA and flashing.

Flame not detected

Check Action

1. Is burner flame visible? yes: ↓5.

no: ↓2.

2. Is the gas cock turned on? yes: ↓3.

no: B Turn on the gas cock.

B Press , does appliance restart???

EA? ↓3.

3. Did the thermal security of the gas cock lock out?

yes: B ...

no: ↓ ...

4. ...

5. Is there a problem with the flue? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check the flue.

no: ↓ ....

... ...

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4.4 Faults indicated on display

A1 flashing.

Controlled-characteristic pump has run dry

Check Action

1. System pressure below 1.2 bar? yes: B Power OFF the appliance.

B Check appliance and system for water leaks and

repair as necessary.

B Top up system. B Turn ON the appliance.

A1? ↓2.

no: ↓2.

2. Activate venting sequence. B Activate menu option Show service parameters.

B Select 7.3 Aeration mode select setting On,

autom. deactivat. and confirm.

B Vent appliance

B Vent radiators.

↓3.

1) See installation instructions

3. Audible bearing damage on pump? yes: B Power OFF the appliance.

B Drain appliance. B Replace pump. B Top up system. B Turn ON the appliance.

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A5 flashing.

Heat store NTC sensor 2 defective

Check Action

1. B Activate menu option

Show service parameters.

B Select

.4 Stor.tank temp.sensor2 . Is a temperature between 0. and 5. displayed?

yes: B Is the connector for heat store NTC sensor 2 cor-

roded

, damaged or dirty? Replace affected

components.

↓2.

1) For notes, refer to Appendix.

no: ↓3.

2. B Disconnect connector for heat store NTC sensor 2.

B Short-circuit the 2-pin connector

on the end of the 20-pin connector lead assembly. After max. 60 sec: Display changes to temperature between 100. and 95.?

yes: B Power OFF the appliance.

B Change heat store NTC sensor 2. B Plug the connection wire. B Turn ON the appliance.

A7? ↓3.

no: B Change the 20-pin connector lead assembly.

↓3.

3. Temperature between 95. and 100. is

displayed. B Unplug the connector.

After max. 60 sec.: Does the displayed code change to a value between 0. and 5.?

yes: B Power OFF the appliance.

B Change heat store NTC sensor 2. B Plug the connection wire. B Turn ON the appliance.

A7? ↓4.

no: ↓4.

4. B Unplug the 20-pin connector lead assembly from the Heatronic. After max. 60 sec.: Does the displayed code change to a value between 0. and 5.?

yes: B Change the 20-pin connector lead assembly.

no: B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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A7 flashing.

Hot water NTC sensor defective

Check Action

1. B Activate menu option

Show service parameters.

B Select

.2 Hot water temp.sensor . Is a temperature between 0. and 5. displayed?

yes: B Is the connector for hot water NTC sensor corro-

ded

, damaged or dirty? Replace affected com-

ponents.

↓2.

1) For notes, refer to Appendix.

no: ↓3.

2. B Disconnect connector for hot water NTC sensor.

B Short-circuit the 2-pin connector

on the end of the 20-pin connector lead assembly. Display changes to temperature between 100. and 95.?

yes: B Power OFF the appliance.

B Change hot water NTC sensor. B Plug the connection wire. B Turn ON the appliance.

A7? ↓3.

no: B Change the 20-pin connector lead assembly.

↓3.

3. Temperature between 95. and 100. is

displayed. B Unplug the connector.

After max. 60 sec.: Does the displayed code change to a value between 0. and 5.?

yes: B Power OFF the appliance.

B Change hot water NTC sensor. B Plug the connection wire. B Turn ON the appliance.

A7? ↓4.

no: ↓4.

4. B Unplug the 20-pin connector lead assembly from the Heatronic. After max. 60 sec.: Does the displayed code change to a value between 0. and 5.?

yes: B Change the 20-pin connector lead assembly.

no: B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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A8 flashing.

No correct electrical connection

Check Action

1. Mode selector switch is between two settings

B Turn switch until it clicks into position.

A8? ↓2.

2. B Power OFF the appliance. Wiring between TR 2 and text-

display OK?

• Terminal 3 on TR 2 connected to

Terminal 3 on textdisplay ?

• Terminal 4 ... Terminal 4 ....

etc.

yes: B Turn ON the appliance.

↓3.

no: B Rewire correctly as specified in the installation

instructions.

B Turn ON the appliance.

after 90 sek.: A8? ↓3.

3. Lead(s) defective. B Check leads for continuity and replace as

necessary.

A8? ↓4.

4. TR 2 defective. B Power OFF the appliance.

B Change TR 2 . B Turn ON the appliance.

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Ad flashing.

Heat store NTC sensor 1 not detected

Check Action

1. Is lead for heat store NTC sensor

correctly routed, i.e. not through cable clamp?

yes: ↓2.

no: B Route connecting lead for heat store tempera-

ture sensor as specified in installation instructions.

2. B Activate menu option

Show service parameters.

B Select

.3 Stor.tank temp.sensor1 . Is a temper ature between 0. and 5. displayed?

yes: Connector on end of NTC sensor lead:

B Flue gas connector corroded

, damaged or

dirty? Change relative parts.

B Press button .

Ad? ↓3.

no: ↓4.

3. Heat store -NTC 1: B Unplug connector from PCB con-

trol board.

B Short circuit the connector using

wire jumper. After max. 60 sec: Display changes to temperature between 100. and 95.

yes: B Replace heat store NTC sensor 1.

no: B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

4. Temperature between 95. and 100. is displayed.

B Unplug the connector.

After max. 60 sec.: Does the displayed code change to a value between 0. and 5.?

yes: B Replace heat store NTC sensor 1.

no: B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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b1 flashing.

Code plug not detected.

Check Action

1. No fault or fault code FC displayed

on text display?

yes: B Power OFF the appliance.

B Fit code plug (correctly), making sure code

number (see Appendix) is correct.

B Turn ON the appliance.

b1? ↓2.

no: ↓2.

2. B Activate menu option Show serv- ice parameters.

B Select 1.2 Code plug. B Compare number displayed with

that shown in Appendix. No number or incorrect number (last three digits) displayed.

yes: ↓2.

no: ↓4.

3. Code plug loose, incorrect or defec-

tive.

B Power OFF the appliance. B Replace code plug

, making sure code number

is correct.

B Turn ON the appliance.

b1? ↓4.

1) For order no., refer to Appendix

4. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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C1 flashing.

Fan speed too low

Check Action

1. Fan lead connector properly connected?

yes: ↓2.

no: B Power OFF the appliance.

B Plug in connector. B Turn ON the appliance.

C6? ↓2.

2. Fan lead defective? yes: B Power OFF the appliance.

B Replace fan lead. B Turn ON the appliance.

C6? ↓3.

no: ↓3.

3. Fan defective? yes: B Power OFF the appliance.

B Plug the connection wire. B Replace fan. B Plug the connection wire. B Turn ON the appliance.

C6? ↓4.

no: ↓4.

4. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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d3 flashing.

Wrong signal from pin 8-9.

Check Action

1. Jumper 8 - 9 fitted correctly? yes: ↓2.

no: B Power OFF the appliance.

B Fit jumper 8 - 9 correctly, tighten screw. B Turn ON the appliance.

d3? ↓2.

2. B Turn ON the appliance. B Measure voltage between Termi-

nal 4 and Terminal 8.

24 V DC?

yes: ↓3.

no: ↓5.

3. Heat store NTC sensor connected to terminals 7, 8 and 9?

yes: B Power OFF the appliance.

B Plug heat store NTC sensor connector into PCB

control board (303, page 46, Pos. 303). If lead has no connector: replace heat store NTC sensor.

B Turn ON the appliance.

d3? ↓4.

no: ↓4.

4. Existing heat store thermostat connected to Terminals 7, 8 and 9?

yes: B Power OFF the appliance.

B Fix the additional bridge 8-9 in the right position

and close the screws.

B Turn ON the appliance.

d3? ↓5.

no: ↓5.

5. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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E2 flashing.

The heating outlet NTC sensor is damaged.

Check Action

1. B Activate menu option

Show service parameters.

B Select .1 Flow temp.sensor.

Is a temperature between 0. and 5. displayed?

yes: The heating outlet NTC sensor is in short circuit:

B Power OFF the appliance. B Replace CH flow NTC sensor; observe fitting

instructions for NTC sensor when doing so.

B Turn ON the appliance.

E2? ↓2.

no: ↓ 2.

2. Heating outlet NTC sensor:

Temperature between 95. and 100. is displayed.

yes: The CH flow NTC sensor is interrupted:

B Power OFF the appliance. B Replace CH flow NTC sensor; observe fitting

instructions for NTC sensor when doing so.

B Turn ON the appliance.

E2? ↓3.

no: ↓3.

3. Check if the 20-pin connector lead assembly is damaged.

B Power OFF the appliance. B Change the 20-pin connector lead assembly. B Turn ON the appliance.

E2? ↓4.

4. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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E9 and flashing.

Safety temperature limiter has tripped.

Check Action

1. Is the heating pressure between 1 and 2 bar?

yes: B Top up system.

B Vent appliance. B Press , does appliance restart???

E9?↓2.

no: ↓2.

2. Is the pump blocked? yes: B Unblock the pump.

If pump won’t start:

B Power OFF the appliance. B Disconnect the boiler electrical connection. B Change the pump. B Reconnect the boiler electrical connection. B Turn ON the appliance. B Press , does appliance restart???

E9? ↓3.

no: ↓3.

3. Is lead disconnected from one/both safety temperature limiters?

yes: B Power OFF the appliance.

B Connect lead. B Turn ON the appliance. B Press , does appliance restart???

E9? ↓4.

no: ↓4.

4. B Power OFF the appliance. B Unplug the connector from the

cut-off device.

B Measure the NTC electrical resist-

ance.

R = ∞?

yes: B Change the over heating cut-off device.

B Connect flue gas safety temperature limiter lead. B Turn ON the appliance. B Press , does appliance restart???

E9? ↓5.

no: B Connect flue gas safety temperature limiter lead.

B Turn ON the appliance.

E9? ↓5.

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5. B Power OFF the appliance. B Remove fuse SI 3 from appliance

PCB control board and test for continuity.

R = ∞?

yes: B Change the fuse.

B Turn ON the appliance. B Press , does appliance restart???

E9? ↓6.

no: B Remount the fuse.

B Turn ON the appliance.

6. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

E9 and flashing.

Safety temperature limiter has tripped.

Check Action

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EA and flashing.

During operation: flame not detected

Check Action

1. Is the flame present? yes: ↓6.

no: ↓2.

2. Is the gas cock open? yes: ↓3.

no: B Open the gas cock

B Press , does appliance restart???

EA? ↓3.

3. Is there air in the supply pipe? yes: B Vent supply pipe.

B Press , does appliance restart???

EA? ↓4.

no: ↓4.

4. Did the thermical security of the gas cock lock out?

yes: B Reset security.

B Press , does appliance restart???

EA? ↓5.

no: ↓5.

5. Natural gas models: does the building have a supply pressure regulator?

yes: B Check that it is fitted correctly and functioning

properly and correct if necessary.

B Check supply pressure, inform gas company if

outside correct range.

B Press , does appliance restart???

EA? ↓6.

no: ↓6.

LPG models:

is the flow rate of the gas supply to the appliance correct?

yes: ↓6.

no: B Is there enough gas in the supply cylinder?

B Is there air in the supply pipe? B Is the solenoid valve in the “meter cabinet” open-

ing?

B Is the supply pressure OK? (if the supply pres-

sure is too high, check the pressure regulator in the “meter cabinet” and on the LPG supply cylinder).

B Press , does appliance restart???

EA? ↓6.

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6. Is the ground connection correct? yes: ↓7.

no: B Rewire correctly as specified in the installation

instructions.

B Press , does appliance restart???

EA? ↓7.

7. Two phase net: Is there a resistor fitted between Pe and N?

yes: ↓8.

no: B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Insert resistance (Order no. 8 900 431 516)

between the ground and the N connection.

B Reconnect the boiler electrical connection. B Turn ON the appliance. B Press , does appliance restart???

EA? ↓10.

8. Is condensation trap in condensing boiler blocked?

yes: B Unscrew condensation trap and clean.

B Press , does appliance restart???

EA? ↓12.

no: ↓9.

9. Check the gas valve?

B Power OFF the appliance. B Unplug the connectors from the

gas valve.

B Measure the gas valve coils I and

II electrical resistance.

R =164 ± 40 Ω?

yes: B Reconnect the gas valve.

B Turn ON the appliance. B Press , does appliance restart???

EA? ↓10.

no: B Change the gas valve.

B Reconnect the gas valve. B Turn ON the appliance. B Press , does appliance restart???

EA? ↓10.

10. Is flue blocked? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check the flue.

B Press , does appliance restart???

EA? ↓11.

no: ↓11.

EA and flashing.

During operation: flame not detected

Check Action

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7 181 465 347 (01.07)30

Rectifying faults

11. Is flue gas CO

level incorrect1) ? yes: B Adjust to correct level.

B Press , does appliance restart???

EA? ↓12.

no: ↓12.

12. B Activate menu option Show serv- ice parameters.

B Select 5.1 Permanent ignition. Continuous ignition OK?

yes: ↓13.

no: ↓16.

13. Ignition lead connected to ignition

electrodes?

yes: ↓14.

no: B Connect cable to ignition electrode.

B Press , does appliance restart???

EA? ↓14.

14. Ignition cable connector engaged in

switchbox?

yes: ↓15.

no: B Power OFF the appliance.

B Engage ignition cable connector in switchbox. B Turn ON the appliance. B Press , does appliance restart???

EA? ↓15.

15. Ignition cable defective? yes: B Power OFF the appliance.

B Replace ignition cable. B Turn ON the appliance. B Press , does appliance restart???

EA? ↓16.

no: ↓16.

16. B Select 3.3 Ionisation current.

Measured ionisation current medium or high?

yes: ↓18.

no: ↓17.

EA and flashing.

During operation: flame not detected

Check Action

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7 181 465 347 (01.07)

Rectifying faults

17. Electrode assembly defective?

B Power OFF the appliance. B Remove electrode assembly.

Electrodes worn out?

yes: B Replace electrode assembly.

B Turn ON the appliance. B Press , does appliance restart???

EA? ↓18.

no: B Refit electrode assembly.

B Turn ON the appliance. B Press , does appliance restart???

EA? ↓18.

18. Check if the 20-pin connector lead assembly is damaged.

B Power OFF the appliance. B Change the 20-pin connector lead assembly. B Turn ON the appliance. B Press , does appliance restart???

EA? ↓19.

19. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

1) See installation instructions

EA and flashing.

During operation: flame not detected

Check Action

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7 181 465 347 (01.07)32

Rectifying faults

F0 (and possibly ) flashing.

Internal failure

Check Action

1. B Activate menu option

Show service parameters.

B Select 9.3 GFA-Asic-error.

A message is displayed.

B Record figure displayed in service report.

↓2.

2. B Select 5.2 GFA status / error.

A message is displayed.

B Record figure displayed in service report.

3. B Select Settings -> Service -> Further options -> Fault history.

Other faults apart from F0 displayed?

yes: B Deal with fault(s) displayed as instructed in rele-

vant fault table(s) .

no: ↓3.

4. flashing? yes: B Press button .

B Initiate demand for heat by pressing the . but-

ton and then cancel after 30 seconds by pressing the button again.

B Initiate demand for heat twice more as described

above.

F0? ↓4.

no: ↓4.

5. The PCB control board is damaged. B Power OFF the appliance.

B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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7 181 465 347 (01.07)

Rectifying faults

F7 and flashing.

Although appliance switches off, flame still detected

Check Action

1. Electrode(s) dirty or defective. B Power OFF the appliance. B Replace electrode assembly. B Turn ON the appliance. B Press , does appliance restart???

F7? ↓2.

2. B Power OFF the appliance.

B Disconnect the boiler electrical

connection. B Remove PCB control board. PCB control board damp?

yes: B Dry PCB control board (e.g. with hair dryer).

B Refit PCB control board. B Reconnect the boiler electrical connection. B Press , does appliance restart???

F7? ↓3.

no: ↓3.

3. Is there a problem with the flue? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check flue and repair or replace if necessary.

no: ↓4.

4. The PCB control board is damaged. B Power OFF the appliance. B Disconnect the boiler electrical connection. B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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7 181 465 347 (01.07)34

Rectifying faults

FA and flashing.

After appliance switches off flame is detected

Check Action

1. Is condensation trap in condensing boiler blocked?

yes: B Clean condensation trap discharge pipe.

B Press , does appliance restart???

FA? ↓2.

no: ↓2.

2. Electrodes faulty. B Replace electrode assembly.

B Turn ON the appliance. B Press , does appliance restart???

FA? B Power OFF the appliance.

↓3.

3. Problem with flue? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check flue and repair or replace if necessary.

B Press , does appliance restart???

FA? B Power OFF the appliance.

↓4.

no: ↓4.

4. The gas valve is damaged. B Change the gas valve.

B Turn ON the appliance. B Press , does appliance restart???

FA? B Power OFF the appliance.

↓5.

5. Check if the 20-pin connector lead assembly is damaged.

B Change the 20-pin connector lead assembly. B Turn ON the appliance. B Press , does appliance restart???

FA? B Power OFF the appliance.

↓6.

6. The PCB control board is damaged. B Disconnect the boiler electrical connection.

B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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7 181 465 347 (01.07)

Rectifying faults

FC flashing.

Text display module not detected

Check Action

1. No fault or fault code FC displayed

on text display?

B Power OFF the appliance. B Fit code plug (correctly), making sure code

number is correct (see Appendix).

B Turn ON the appliance.

FC? ↓2.

2. B Unplug text display module connector.

B Connecting lead between text dis-

play module and Heatronic OK.?

yes: B Plug in connector.

FC? ↓3.

no: B Replace text display module.

FC? ↓3.

3. Text display module defective. B Replace text display module.

Fd and flashing.

Reset button pressed inadvertently

Check Action

1. B Press button again.

2. The PCB control board is damaged. B Disconnect the boiler electrical connection.

B Change PCB control board. B Reconnect the boiler electrical connection. B Turn ON the appliance.

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7 181 465 347 (01.07)36

Rectifying faults

4.5 Faults that are not displayed

4.5.1 Appliance faults

Boiler indicates P1, P2, P3 at start-up and then restarts with P1..

Check Action

1. Fuse T 1.6 A (312) defective. yes: B Turn ON the appliance.

B Change the fuse. B Power OFF the appliance.

Start sequence not completed? ↓2.

no: ↓2.

2. The PCB control board is damaged. B Change PCB control board.

Excessive burner noise, rumbling noises

Check Action

1. Does the gas supply type match the specifications on the appliance identification plate?

yes: ↓2.

no: B Convert appliance to correct gas type

2. B Test gas supply pressure - OK?

? yes: ↓3.

no: B Decommission appliance.

B Notify gas company.

3. Problem with flue? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check flue and repair or replace if necessary.

no: ↓4.

4. B Remove silencer, flue pipe and mixer unit. Is internal flue pipe/silencer dirty or clogged or are seals defective or incorrectly fitted?

yes: B Repair or replace components.

B Grease seal before fitting, B Make sure it is fitted in correct position.

no: ↓5.

5. Flue gas CO

levels measured at min. and max. load do not match specified levels

B Measure CO

levels.

yes: B Adjust CO

levels.

no: B Power OFF the appliance.

B Change the gas valve. B Turn ON the appliance.

1) See installation instructions

Page 89

7 181 465 347 (01.07)

Rectifying faults

Flue gas levels incorrect, CO level too high

Check Action

1. Does the gas supply type match the specifications on the appliance identification plate?

yes: ↓2.

no: B Convert appliance to correct gas type

2. B Test gas supply pressure

, - OK? yes: ↓3.

no: B Decommission appliance.

B Notify gas company.

3. Problem with flue? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check flue and repair or replace if necessary.

no: ↓4.

4. Flue gas CO

levels measured at min. and max. load do not match specified levels?

B Measure CO

levels.

yes: B Adjust CO

levels.

no: ↓5.

5. Gas volumetric flow too high when CO

level correctly set1).

yes: B Reduce gas volumetric flow rate by means of

adjusting screw on gas valve and/or gas flow restrictor.

B Check CO

adjustment.

no: ↓6.

6. B Change the gas valve.

1) See installation instructions

Page 90

7 181 465 347 (01.07)38

Rectifying faults

Ignition too harsh, ignition poor

Check Action

1. B Activate menu option

Show service parameters.

B Select 5.1 Permanent ignition.

Continuous ignition OK?

yes: ↓6.

no: ↓2.

2. Ignition lead connected to ignition electrodes?

yes: ↓3.

no: B Connect cable to ignition electrode.

B Press button .

Ignition poor? ↓3.

3. Ignition cable connector engaged in switchbox?

yes: ↓4.

no: B Power OFF the appliance.

B Engage ignition cable connector in switchbox. B Turn ON the appliance. B Press button . B Power OFF the appliance.

Ignition poor? ↓4.

4. Ignition cable defective? yes: B Power OFF the appliance.

B Replace ignition cable. B Turn ON the appliance. B Press button . B Power OFF the appliance.

Ignition poor? ↓5.

no: ↓5.

5. Electrode assembly defective?

B Power OFF the appliance. B Remove electrode assembly.

Electrodes worn out?

yes: B Replace electrode assembly.

B Turn ON the appliance. B Press , does appliance restart???

Ignition poor? ↓6.

no: B Refit electrode assembly.

B Turn ON the appliance. B Press , does appliance restart???

Ignition poor? ↓6.

6. Does the gas supply type match the specifications on the appliance identification plate?

yes: ↓7.

no: B Carry out gas type conversion as described in

installation instructions.

Ignition poor? ↓7.

Page 91

7 181 465 347 (01.07)

Rectifying faults

7. B Test gas supply pressure

- OK?. yes: ↓8.

no: B Decommission appliance.

B Notify gas company.

8. Problem with flue? B Check CO

level in combustion air. > 0,2 % CO

yes: B Check flue and repair or replace if necessary.

Ignition poor? ↓8.

no: ↓9.

9. Flue gas CO

levels measured at min. and max. load do not match specified levels.

B Measure CO

levels.

yes: B Adjust CO

levels.

no: ↓9.

10. Burner not correctly fitted or defective?

B Remove burner.

Cover fixings not tight

seal defective or not correctly fitted

burner defective.

B Replace burner and seal if necessary B Ensure seal is fitted in correct position.

1) See installation instructions

Ignition too harsh, ignition poor

Check Action

Loose or broken contact on heat store NTC sensor

Check Action

Heat store NTC sensor lead is not fitted as described in the installation instructions (i.e. the cable does not pass through the cable grip in the switchbox).

B Record condition of appliance as found in custo-

mer service record.

B Route cable as specified in installation instruc-

tions.

Text display fails to respond, no display or display incorrect

Check Action

Ignition lead is not fitted as specified in installation instructions (i.e. the lead should be routed through the clip on the underside of the air box).

B Route cable as specified in installation instruc-

tions.

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7 181 465 347 (01.07)40

Rectifying faults

Specified CH flow temperature from TA... programmer exceeded

Check Action

If outside-temperature controlled programmer (TA...) is connected to boiler:

• The anti-cycle time is adjusted by the programmer to the suit the system.

• The factory setting for the anti-cycle time (3 min.) and the heating mode hysteresis setting, if applicable, are deactivated.

• In cyclic mode, the switching of the boiler on or off is subject to a time delay in order to prevent divergence between the average CH flow temperature and the specified CH flow temperature. As a result (depending on the heat draw), the specified CH flow temperature is briefly exceeded. In extreme cases, it can happen that the burner does not switch off until the maximum CH flow temperature is reached even though a lower CH flow temperature has been specified.

1. B Activate menu option

Show service parameters.

B Select 2.7 Autom. anti-cycle

mode.

Read off status of automatic anticycle time (0 = Disabled, 1=Enabled)

B Disable automatic anti-cycle time, i.e. change

setting to 0.

2. B Select 2.4 Anti-cycle mode.

Read off anti-cycle time setting ( 0 ... 15 min)

B Set anti-cycle time as required, e.g. factory set-

ting 3 min.

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7 181 465 347 (01.07)

Rectifying faults

4.5.2 Programmer faults

Set room temperature not reached (TR 2)

Check Action

1. Thermostatic valve(s) set too low? yes: B Turn up thermostatic valve(s).

↓2.

no: ↓2.

2. CH flow temperature control on boiler set too low?

yes: B Turn up CH flow temperature control.

no: ↓3.

3. Air in the heating system. B Power OFF the appliance.

B Check appliance and system for water leaks and

repair as necessary.

B Top up system. B Activate menu option Show service parame-

ters.

B Select 7.3 Aeration mode , select setting On,

autom. deactivat. and confirm.

B Vent appliance

B Vent radiators. B Turn ON the appliance.

1) See installation instructions

Page 94

7 181 465 347 (01.07)42

Rectifying faults

Set room temperature not reached

Check Action

1. Thermostatic valve(s) set too low? yes: B Turn up thermostatic valve(s).

↓2.

no: ↓2.

2. Heating characteristic set too low? yes: B Correct heating characteristic.

↓3.

no: ↓3.

3. CH flow temperature control on boiler set too low?

yes: B Turn up CH flow temperature control.

↓4.

no: ↓4.

4. Heat store connected via HSM? yes: ↓5.

no: ↓6.

5. Is heat store temperature unreachable (CH flow temperature control set too low)?

yes: B Turn up CH flow temperature control.

↓6.

no: ↓6.

6. Air in the heating system. B Power OFF the appliance.

B Check appliance and system for water leaks and

repair as necessary.

B Top up system. B Activate menu option Show service parame-

ters.

B Select 7.3 Aeration mode , select setting On,

autom. deactivat. and confirm.

B Vent appliance

B Vent radiators. B Turn ON the appliance.

1) See installation instructions

Page 95

7 181 465 347 (01.07)

Rectifying faults

Set room temperature exceeded by large amount

Check Action

1. Do radiators get too hot? yes: TR 2:

B Decrease setting of “Heating” control

↓2.

no: ↓2.

2. Bad choice of location for programmer, e.g. outside wall, near window, in draught, on hollow wall, etc.

yes: B Select better installation location

↓3.

no: ↓3.

3. B Turn down thermostatic valve(s).n

1) See installation instructions

Temperature rises instead of falling

Check Action

Timer clock (DT 2) incorrectly set B Check setting and correct as necessary.

Room temperature too high in Economy mode

Check Action

Building retains heat well yes: B Set economy temperature lower.

-or-

B Set earlier start time for Economy mode.

Incorrect or no modulation

Check Action

Programmer incorrectly wired B Check wiring against wiring diagram and correct

as necessary.

Page 96

7 181 465 347 (01.07)44

Rectifying faults

Heat store fails to heat up

Check Action

1. with TR 2: CH flow temperature control on boiler set too low.

B Increase CH flow temperature control setting.

2. Hot water temperature control on boiler set too low

B Increase hot water temperature control setting.

Page 97

7 181 465 347 (01.07)

Appendix

5Appendix

5.1 NTC values

5.1.1 Outside temperature sensor

5.1.2 CH flow NTC sensor, heat store NTC sensor, constant hot water NTC sensor and hot water NTC sensor

Outside temperature

(°C)

Measurement

tolerance ± 10%

Resistance

( Ω)

-20 2 392

-16 2 088

-12 1 811

-8 1 562

-4 1 342

01 149

4984

8842

10 781

15 642

20 528

25 436

Table 5

Temperature ( °C)

Measurement

tolerance ± 10%

Resistance

( Ω)

20 14 772

25 11 981

30 9 786

35 8 047

40 6 653

45 5 523

50 4 608

55 3 856

60 3 243

65 2 744

70 2 332

75 1 990

80 1 704

85 1 464

90 1 262

95 1 093

100 950

Table 6

Page 98

7 181 465 347 (01.07)46

Appendix

5.2 Electronic schemes

Fig. 2

4.1 Ignition transformer 6 Temperature limiter, heat exchanger 9 Flue gas temperature limiter 18 Pump 32 Flame sensing electrode 33 Ignition electrode 36 Temperature sensor in CH flow 52 Solenoid valve 1

52.1 Solenoid valve 2 56 Gas valve CE 427 61 Reset button 84 Motor, 3-way valve (ZSBR) 135 Master switch 136 Temperature control for CH flow 151 Fuse, slow 2.5 A, AC 230 V 153 Transformer 161 Link

226 Fan 300 Code plug 302 Earth connection 310 Temperature control for hot water 312 Fuse, slow T 1,6 A 313 Fuse, slow T 0,5 A 317 Digital display 328 Terminal block for AC 230 V Mains supply

328.1 Link 363 Indicator lamp for burner 364 Indicator lamp for power supply 365 “Chimney sweep” button 366 Service button 367 ECO button 400 Textdisplay 422 Connecting TR2

52.1

230 V

135

25 V

230V/AC

153

136

151

1247

161

226

300

NLsNs

328

302

310

312

313

317

363

364

365

366

ECO

367

4.1

328.1

400

43F

6 720 610 603 - 03.1O

mains supply

422

r r

bl bl bl bl

p p

o - orange bl - black r - red p - purple

Page 99

7 181 465 347 (01.07)

Appendix

5.3 List of most important replacement parts

Component Order no. Remarks

Switchbox

PCB control board

8 748 300 385

Transformer 8 747 201 358

Ignition lead 8 714 401 878

20-pin connector lead assembly

8 714 401 912

Fuse 1 904 522 730 T 0,5 A

Fuse 1 904 522 740 T 1,6 A

Fuse 1 904 521 342 T 2,5 A

Code plug included in

Conversion kit G20 -> 31

7 710 149 050 ZWBR

8-30

Conversion kit G31 -> G20

7 710 239 086 ZWBR

11- 30

Conversion kit G20 -> G31

7 710 149 051 ZWBR

11 - 37

Conversion kit G31 -> G20

7 710 239 087 ZWBR

14 - 37

Conversion kit G20 -> G31

7 710 149 052 ZSBR

7-28

Conversion kit G31 -> G20

7 710 239 088 ZSBR

11-28

Conversion kit G20 -> G31

7 710 149 053 ZBR 8-35

Conversion kit G31 -> G20

7 710 239 089 ZBR 11-35

Conversion kit G20 -> G31

7 710 149 046 ZWBR

7-28

Conversion kit G31 -> G20

7 710 239 082 ZWBR

11-35

Conversion kit G20 -> G31

7 710 149 047 ZWBR

11-35

Conversion kit G31 -> G20

7 710 239 083 ZWBR

14-35

Table 7

Heat exchanger

Temperature limiter STB

8 729 000 144 110 °C

Flue gas temperature limiter

8 729 000 144

Temperature sensor, CH flow

8 714 500 054 NTC

Burner

Electrode assembly

8 718 107 064

Gas valve

Gas valve 8 747 003 516

Gas valve 8 747 003 515 ZBR 11/

14..42A

Other components

Fan 8 717 204 325

Gas supply pipe 8 714 401 885

Textdisplay 8 747 208 081

Plate-type heat exchanger

8 715 406 659 ZWBR

7/11-28 A.

Component Order no. Remarks

Table 7

Page 100

7 181 465 347 (01.07)48

Appendix

5.4 Approved corrosion inhibitors and anti-freeze fluids for central heating water

Manufacturer Description Remarks

Mixing concentra– tion % by weight

With all anti-freeze fluids and corrosion inhibitors, it is extremely important to observe the manufacturer’s recommended concentration levels and to check the concentration regularly. In the case of anti-freeze fluids, it should be noted that the efficiency of fluid-to-fluid heat transfer diminishes as the anti-freeze concentration increases.

Anti-freeze fluid

Hüls Ilexan E Anti-freeze fluid, equivalent to Antifrogen N.

Tyforop Chemie GmbH, Hamburg

Tyfocor L Anti-freeze fluid based on propylene glycol. 25-80

Schilling Chemie Varidos FSK Anti-freeze fluid based on ethylene glycol with

good corrosion-inhibiting properties. Also suitable for aluminium.

22-55

Hoechst Antifrogen N Anti-freeze fluid based on ethylene glycol with

good corrosion-inhibiting properties.

20-40

Fernox Alphi-11 Anti-freeze fluid with corrosion inhibitor, also suit-

able for aluminium.

BASF Glythermin NF Anti-freeze fluid based on ethylene glycol with

good corrosion-inhibiting properties, also suitable for aluminium.

20-62

Corrosion inhibitor

Schilling Chemie Varidos KK Corrosion inhibitor 0,5

Schilling Chemie Varidos 1+1 Corrosion inhibitor 1-2

Schilling Chemie Varidos AP Corrosion inhibitor, also suitable for aluminium. 1-2

Benckiser Wassertechnik

Randophos HS Universal

Corrosion inhibitor

Geminox, Frankreich

Inibal Corrosion inhibitor, suitable for aluminium. 1-2

Betz Dearborn, Belgien

Sentinel X 100 Corrosion inhibitor for hot water heating systems,

also suitable for aluminium.

1,1

Fernox Copal Corrosion inhibitor, also suitable for aluminium. 1

Cillit Wassertechnik Cillit-HS Combi Corrosion inhibitor 0,5

Other additives

Fernox Restorer Superfloc

Universal Cleanser

Cleaning agent (for sludge removal), also suitable for aluminium.

1-2

Fernox Superconcentrate

Central heating Protector

Reduces limescale precipitation, also suitable for aluminium.

Table 8