Worcester 28CDi RSF, Installation And Servicing Instructions

Page 1: ...BOILER OUTPUT Automatic Modulating Control To Domestic Hot Water To Central Heating Minimum 9 0 kW 9 0 kW Maximum 28 0 kW 24 0 kW IMPORTANT THESE INSTRUCTIONS APPLY IN THE UK ONLY THESE INSTRUCTIONS ARE TO BE LEFT WITH THE USER OR AT THE GAS METER This appliance must be installed by a competent person in accordance with the Gas Safety Installation and Use Regulations 1994 Bosch Group ...

Page 2: ...ting load 2 3 The control circuit provides direct burner ignition A pilot is not used 2 4 PRINCIPAL APPLIANCE COMPONENTS See Fig 1 A low thermal capacity Gas to Water heat exchanger A Water to Water heat exchanger to provide domestic hot water Fully modulating controls in the central heating and domestic hot water modes of operation An expansion vessel pressure gauge and pressure relief valve A by...

Page 3: ...or where it would cause a hazard to the user A drain cock to BS 2879 must be fitted to the lowest point of the system For circuit design purposes it is important that due note is taken of the information given in Table 3 relating to the available pump head 2 12 SHOWERS BIDETS TAPS AND MIXING VALVES Hot and cold taps and mixing valves used in the system must be suitable for operating at mains press...

Page 4: ...INIMUM COLD SUPPLY PRESSURE working for max hot water flow 1 2 bar MINIMUM COLD SUPPLY PRESSURE working to operate appliance 0 7 bar MAXIMUM CENTRAL HEATING FLOW TEMPERATURE Nominally 82 C 180 F OUTPUT TO DOMESTIC HOT WATER Modulating 9 0 to 28 kW OUTPUT TO CENTRAL HEATING Modulating 9 0 to 24 kW MAXIMUM DOMESTIC HOT WATER FLOW RATE from the appliance Nominally 10 litres min EQUIVALENT DOMESTIC HO...

Page 5: ...upply are maintained 4 7 The airing space must be separated from the boiler space by a perforated non combustible partition Expanded metal or rigid wire mesh are acceptable provided that the major dimension is less than 13mm See BS 6798 1987 4 8 No combustible surface must be within 75mm of the casing See BS476 4 4 9 The distance between the inner face of a cupboard door and the cabinet front shou...

Page 6: ...are given in Section 4 Siting The Appliance then permanent air vents for cooling are required One at high level and one at low level either direct to outside air or to a room Both vents must pass to the same room or be on the same wall to the outside air 6 4 The minimum free areas required are given below 6 5 Refer to BS 6798 and BS 5440 2 for additional information 6 Air Supply 5 Siting The Flue ...

Page 7: ...rey knob anti clockwise to allow water ingress and fill until the required pressure is reached Turn the grey knob clockwise to stop filling and remove the filling key by lining up the bayonet end of the key with the cutouts in the filling loop housing and withdrawing the key N B The key must always be removed from the filling loop housing after the system has been filled to prevent accidental fill...

Page 8: ...mer weather 9 8 It is suggested that long pipe runs to the taps or shower should be insulated to prevent the rapid cooling of domestic hot water after a tap or shower has been turned off 9 9 Hot and cold taps and mixing valves used with this appliance must be suitable for operating at mains pressure and temperatures of 65 C 9 10 No anti syphonage arrangements are necessary except for some loose he...

Page 9: ... Figs 11 12 and 13 The devices must be suitable for use with mains voltage 10 8 Facia mounted programmers are available as optional extras Instructions are supplied with the programmer kits 10 9 A time switch or programmer can be fitted externally to the appliance 10 10 The boiler is fitted with an internal frost thermostat which will protect the boiler from frost damage as long as the mains switc...

Page 10: ...ectronics Electronics Electronics Electronics Inputs Outputs Spark Indicators Settings Regulator valve CH demand indicator Red Spark electrodes DHW demand indicator Red Flame detect indicator Red Main valve Main valve Flow switch CH sensor DHW sensor Air pressure switch Flame sense Overheat cut off 24V programmer Reset button Gas valve mode switch CH pressure adjust pot CH Control knob DHW control...

Page 11: ...and programmer connections Fig 12 230 V programmer connections NS LS ST8 ST8 ST8 Remove link Neutral Live Switched live Neutral Neutral S w i t c h e d l i v e L i v e Live S w i t c h e d l i v e LR Spare NS LS LR Spare Spare Motor Neutral Live Switched live NS LS LR Motor ...

Page 12: ...andard flue duct 7 Restrictor ring 8 Flue terminal 9 Extension air duct 10 Extension flue duct 11 Flue duct sealing ring 12 In line flue elbow 13 Vertical flue adaptor IMPORTANT The restrictor ring must not be used for flue lengths over 650mm The flue must be installed as specified in BS 5440 Part 1 11 Installation 12 Fig 15 Fixing the appliance to the wall mounting plate Fig 16 Flue turret fixing...

Page 13: ... at this stage before fitting the flue elbow to the appliance Refer to Section 11 3 following for the assembly of the air and flue ducts Remove the fan See Section 14 3 e 11 3 AIR AND FLUE DUCT PREPARATION AND ASSEMBLY Check the contents of the standard flue duct kit against the packing list Similarly check the extension duct kits if applicable Remove all the packing from the ducts and terminal as...

Page 14: ...e the flue centering ring onto the air duct and tighten the screw See Fig 22 Fix the ducts and terminal assembly to the flue turret as described in Section 11 4 preceding Push the assembly through the wall so that the gasket flange is against the outside face of the wall See Fig 22 14 Fig 22 Duct and terminal assembly for internal fitting of the flue Fig 21 Terminal assembly for internal fitting o...

Page 15: ...water and gas connections have been tightened If a facia mounted programmer is to be fitted follow instructions with the programmer Hinge down the facia as described in Section 14 3 c Connect the mains electrical supply to the appliance at terminal ST 12 See Fig 8 Connect any room and or frost thermostats The electrical leads must pass through the appropriate space in the control panel and be fixe...

Page 16: ...ent to a static head of 5 metres 17 ft The charge pressure must not be less than the static head at the point of connection See Fig 7 A Schraeder type tyre valve is fitted to the expansion vessel to allow the charge pressure to be increased if necessary Set the System Pressure Remove the bottom panel to gain access to the filling loop assembly Insert the bayonet end of the filling key into the cor...

Page 17: ... the appliance has cooled to a pre set temperature Set the operating switch to OFF Central Heating Set the mode switch to the normal position Check that all the radiator valves are open Set the room thermostat and the Central Heating Temperature Control to maximum On sealed systems check that the system is pressurised and set to the required pressure as indicated on the gauge Set the Operating Swi...

Page 18: ...beintothemeasurementgapuptoadepthof50mm Seal any gaps Expected measurements should be between CO 0 001 and 0 003 CO2 6 7 and 7 0 After taking the measurement Replace and tighten the sealing screw Turn the Mode Switch back to the normal position Put the facia back in to the correct position IMPORTANT Disconnect the electrical supply at the mains and turn off the gas supply at the gas service cock o...

Page 19: ...ectricity and gas supplies before replacing any components After the replacement of any components check for gas soundness where relevant and carry out functional checks as described in Section 12 Commissioning 15 2 COMPONENT ACCESS To replace components it is necessary to remove one or more sections of the cabinet and cover plates within the appliance as described in Section 14 3 The facia panel ...

Page 20: ...aking care not to damage the electrode leads 9 Burner Injector See Fig 29 Remove the burner as described in Section 14 3 h Unscrew the brass injector from the burner Fit the replacement injector in the reverse order 10 Spark Electrode Assembly See Fig 29 Remove the combustion chamber front and sides as described in 14 3 g Carefully pull off the two electrode leads Undo the M4 extended nut and remo...

Page 21: ...as described in Sections 15 3 a and b Hinge down the facia assembly in the servicing position as described in Section 14 3 c Remove the Bottom panel water to water heat exchanger micro switch assembly and filling loop as described in Section 14 3 d and 15 4 20 and 24 Undo all the water connections to the valve Fit the replacement valve in the reverse order ensuring that the filter and all fibre wa...

Page 22: ... Grundfoss Ref 50 50 6500 1 8 716 143 108 0 25 173 001 Expansion Vessel Zilmet Ref 301010 1 8 716 142 514 0 42 E00 711 Water to Water Heat Exchanger Giannoni Ref PVW 14 E 1 8 716 142 903 0 34 173 005 Diverter Valve Giannoni Ref V37 OM I F 4 A spec D2109 1 8 716 156 746 0 104 394 291 DHW Flow Restrictor Type E 10 litre 1 8 716 141 057 0 105 Domestic Water Filter MPM V3326 1 8 716 148 400 0 109 E01 ...

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Page 27: ... which represents the light situation during your fault Then refer to the appropriate following section This fault finding system assumes that the appliance has been operating correctly until the time of failure PRELIMINARY CHECKS Preliminary electrical system checks are the first electrical checks to be carried out during a fault finding procedure On completion of the Service Fault Finding task w...

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Page 36: ...anged in the interests of continued improvement All goods sold are subject to our official Conditions of Sale a copy of which may be obtained on application PUBLICATION 8 716 145 020d 02 20 Bosch Group Worcester Heat Systems Limited Cotswold Way Warndon Worcester WR4 9SW Telephone 01905 754624 Fax 01905 754619 Technical Helpline 0990 266241 ...