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INSTALLATION, COMMISSIONING, AND SERVICING INSTRUCTIONS
WALL HUNG RSF GAS FIRED CONDENSING COMBINATION BOILER
Greenstar CDi Compact
FOR SEALED CENTRAL HEATING SYSTEMS AND MAINS FED DOMESTIC HOT WATER
ErP
These appliances are for use with:
Natural Gas or L.P.G.
(Cat. II 2H 3P type C13, C33 & C53)
Model
Natural Gas
28CDi Compact
ErP
32CDi Compact
ErP
36CDi Compact
ErP
LPG
28CDi Compact
ErP
32CDi Compact
ErP
36CDi Compact
ErP
If you smell gas:
▶ Well away from the building: call the National Gas
Emergency Service on 0800 111 999.
▶ L.P.G. boilers: Call the supplier's number on the
side of the gas tank.
GC Number
47-406-77
47-406-79
47-406-81
47-406-78
47-406-80
47-406-82
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Related Manuals for Bosch Worcester Greenstar CDi Compact ErP Series
Summary of Contents for Bosch Worcester Greenstar CDi Compact ErP Series
- Page 1 INSTALLATION, COMMISSIONING, AND SERVICING INSTRUCTIONS WALL HUNG RSF GAS FIRED CONDENSING COMBINATION BOILER Greenstar CDi Compact FOR SEALED CENTRAL HEATING SYSTEMS AND MAINS FED DOMESTIC HOT WATER These appliances are for use with: Natural Gas or L.P.G. (Cat. II 2H 3P type C13, C33 & C53) Model GC Number Natural Gas...
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Page 2: Table Of Contents
Contents 5.8.3 Fitting the fascia flap ......39 Contents 5.8.4 Installing bottom panel ......39 5.8.5 Hand over . - Page 3 Key to symbols and safety instructions Key to symbols and safety instructions Key to symbols List entries, first and second levels • A single component/item Warnings • A component/list, made up of multiple parts/items. – Sub component or sublist of main component/list. Warnings in this document are identified by a warning triangle printed against a grey background.
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Page 4: Key To Symbols And Safety Instructions
Key to symbols and safety instructions Health and safety Ø Diameter The appliance contains no asbestos and no substances have been used Natural Gas in the construction process that contravene the COSHH Regulations Liquid Petroleum Gas (Control of Substances Hazardous to Health Regulations 1988). Central Heating Combustion and corrosive materials Domestic Hot Water... - Page 5 Regulations Regulations Installation regulations Current Gas Safety (Installation & Use) Regulations: All gas appliances must be installed by a competent person in accordance with the above regulations. Failure to install appliances correctly could lead to prosecution. The appliance must be installed in accordance with, and comply to, the current: Gas Safety Regulations, IET Regulations, Building Regulations, Building Standards (Scotland) (Consolidation), Building Regulations (Northern Ireland), local water by-laws, Health &...
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Page 6: Appliance Information
APPLIANCE INFORMATION APPLIANCE INFORMATION Appliance Depth to wall 280mm (When fitted to wall frame) 680mm* * 690mm to top of case front 390mm 6720813276-01.1Wo STANDARD PACKAGE 1. Wall hung gas-fired condensing combi boiler for central heating and domestic hot water 2. -
Page 7: Layout
APPLIANCE INFORMATION Layout 6720813276-02.1Wo 48 47 46 45 44 43 42 Fig. 1 Main boiler components CDi Compact - 6 720 813 276 (2015/07) - Page 8 APPLIANCE INFORMATION Wall mounting frame Flow temperature sensor (NTC) Expansion vessel Electrode assembly CH return isolating valve Maximum safety sensor (NTC) DCW mains isolating valve Auto air vent Gas isolating valve Aluminium Silicon Heat exchanger DHW outlet connection Flueway CH flow isolating valve Sump assembly Condensate drain connection Pressure gauge connection point...
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Page 9: Technical Data
APPLIANCE INFORMATION Technical data Natural gas L.P.G. DESCRIPTION CDi Compact ErP UNIT 28kW 32kW 36kW 28kW 32kW 36kW Domestic Hot Water Minimum heat input 7.15 7.15 7.15 7.15 7.15 7.15 Maximum rated heat output Maximum rated heat input 28.57 32.65 36.7 28.57 32.65... -
Page 10: Energy Efficiency
APPLIANCE INFORMATION Energy efficiency Natural gas appliances The following product data satisfy the requirements of the EU Regulations No. 811/2013 and No. 812/2013 supplementing Directive 2010/30/EU. Product data Symbol Unit 7733600053 7733600055 7733600056 Product type – – 28CDi Compact 32CDi Compact 36CDi Compact Condensing boiler –... - Page 11 APPLIANCE INFORMATION LPG appliances The following product data satisfy the requirements of the EU Regulations No. 811/2013 and No. 812/2013 supplementing Directive 2010/30/EU. Product data Symbol Unit 7733600057 7733600058 7733600059 Product type – – 28CDi Compact 32CDi Compact 36CDi Compact Condensing boiler –...
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Page 12: Pre-Installation
▶ In cases where all attempts to find a micro leak have failed, Worcester, Bosch Group supports the use of Fernox F4 leak sealer. CDi Compact... -
Page 13: Water Systems And Pipe Work
PRE-INSTALLATION 4.2.3 Water supply The boiler is equipped with an internal by-pass. Water mains pressure: The internal bypass is not intended to be a substitute for • Minimum mains water pressure for maximum performance: refer to an external system bypass. the Technical data in section 3.3. -
Page 14: Condensate Pipe Work
PRE-INSTALLATION SEALED PRIMARY SYSTEM: Available pump head NOTICE: Artificially softened water must not be used to In order to save as much energy as possible and the fill the central heating system. minimise the possibility of water circulation noise, a low characteristic should be chosen. -
Page 15: Internal Connections
PRE-INSTALLATION 4.4.1 Internal connections In order to minimise risk of freezing during prolonged cold spells, the following methods of installing condensate drainage pipe should be adopted, in order of priority. Wherever possible, the condensate drainage pipe should be routed and terminated so that the condensate drains away from the boiler under 75mm gravity to a suitable internal foul water discharge point such as an... -
Page 16: Pressure Relief Pipe Work
PRE-INSTALLATION ▶ The use of fittings, elbows etc. should be kept to a minimum and any Minimum hole size for the condensate soak away must be internal “burrs” on cut pipe work should be removed so that the 400mm deep by 300mmØ . internal pipe section is as smooth as possible. -
Page 17: Boiler Location And Clearances
PRE-INSTALLATION Pressure relief pipe work Boiler location and clearances 4.6.1 Installation NOTICE: This appliance is only suitable for installing internally within a property at ▶ The pressure relief valve is a safety device for the a suitable location onto a fixed, rigid surface at least the same size as the boiler and if activated may discharge boiling water or appliance and capable of supporting the appliance weight. -
Page 18: Bathrooms
PRE-INSTALLATION 4.6.4 Bathrooms Please check the IP rating of any control to be used on this appliance. Only certain controls can be fitted when the appliance is inside of the shaded area. An appliance with blanking panel or controls that do not change the IP rating can be installed in zone 2. -
Page 19: Flue Options
Flue options Telescopic horizontal flue assembly WARNING: Flue systems 60/100 mm ▶ Only use Worcester, Bosch approved flue systems, 350 mm - 570 mm no other manufacturer’s flue systems have been approved for use with Worcester appliances. CAUTION: Non accessible flue systems: 130 mm Min ▶... - Page 20 PRE-INSTALLATION High level horizontal flue Vertical balanced flue assembly A = 300 mm B = 500 mm Maximum flue length Maximum flue length (mm) (mm) 60/100 80/125 60/100 80/125 Vertical balanced flue assembly 6,000 15,000 High level horizontal flue 6,000 15,000 Table 19 Table 16...
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Page 21: Flue Terminal Positions
PRE-INSTALLATION Flue terminal positions All measurements in millimetres 52mm 104mm 1,500 1,500 300 300 300 300 1,200 Boundary Line Fig. 17 Flue terminal positions NOTICE: ▶ All measurements are the minimum clearances required. ▶ Terminals must be positioned so to avoid combustion products entering the building. ▶... -
Page 22: Plume Management Terminal Positions
PRE-INSTALLATION 4.10 Plume management terminal positions All measurements in millimetres Flue terminal guard 7 716 191 176 ±45° Plume re-direction: 180° Flue Exhaust Outlet 1,500 Air Intake ±80° 1,200 Boundary Line Fig. 18 Plume terminal positions Maximum and minimum plume management lengths: ▶... -
Page 23: Determine The Plume Management System Length
PRE-INSTALLATION 4.10.1 Determine the plume management system length Flue length versus plume management length Effective straight flue length for telescopic flue with plume management Minimum plume length Maximum plume length 500mm (M) 5,000mm (M) Maximum flue length Maximum flue length 5,000mm (L) 2,200mm (L) Note: Measurement M plume length... -
Page 24: Installation
INSTALLATION Additional requirements for roof space installation: INSTALLATION • The boiler should be first unpacked before ascending ladder to a loft space. WARNING: All the previous “Pre-Installation” sections • Two sets of steps should be used. must be read and the requirements met before starting •... -
Page 25: Unpacking The Appliance
INSTALLATION Unpacking the appliance 1. Remove outer carton (1) and place safely away from the working area. 2. Remove the inner sleeve (3) leaving all other cardboard inserts and base (4) in place. 3. Remove the protective wrapping (5) from the boiler. Fig. -
Page 26: Pre-Plumbing Boiler Connections
INSTALLATION ▶ Plumb up to the wall frame with 22mm pipe. ▶ Ensure that there is enough pipe to insert 25mm into the rubber hose connector. ▶ Attach the connector to the condensate drain pipe. 25mm Fig. 28 Condensate connection PRV Pre-plumbing connection 1. - Page 27 INSTALLATION Integral filling link Fit the Integral Filling Link, supplied with the boiler, before hanging the boiler on the frame. Fitting the Filling Link assembly at this stage will be easier than when the boiler is hung on the wall frame. ▶...
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Page 28: Hanging The Boiler
INSTALLATION Hanging the boiler CAUTION: Lifting the boiler ▶ Do not lift the boiler using the control panel as a hand hold. ▶ There are two handling holes incorporated into the inner casing left and right in the lower section of the appliance. -
Page 29: Flue Turret/Adapter Installation
INSTALLATION Connecting the expansion vessel To connect the expansion vessel to the hydraulic pump manifold situated to the left of the pump: 1. Release the expansion tank from the retaining bracket, see fig 37. 2. Ensure that the wire retaining clip on the pump manifold is fully withdrawn, but not removed, before inserting the expansion vessel pipe into pump manifold, see fig. -
Page 30: Electrical
INSTALLATION ▶ Align the flue turret/vertical adaptor to the appliance flue outlet with Access to electrical connections: flat facing [3] to the rear of the appliance. ▶ Access to all wiring connections are via the Installer access cover at The flue turret/adaptor should be pushed straight down, on to the the bottom front of the control panel. -
Page 31: Mounting Optional Plug-In Controls
INSTALLATION Mains voltage connections 230V 230V FR FS LR LR Fig. 44 Mains voltage connectors Mains voltage terminal strip External frost thermostat 230 V A.C. switched live inputs • CH - Remove link when connecting external CH control • DHW - Remove link when connecting external DHW control 230 V A.C. -
Page 32: New Complete System Installations
INSTALLATION THIRD PARTY EXTERNAL TIMER AND TWO ZONES Pre-wired CH & DHW links ▶ Remove link when connecting external CH control ▶ Remove link when connecting external DHW control Zone 1 Zone Valve Zone 1 Zone 2 Zone 2 Room Thermostat Room Thermostat Zone Valve Fig. -
Page 33: Existing Installations
INSTALLATION 5.7.3 Existing installations PROGRAMMABLE THERMOSTAT For boiler replacements on an existing system, it is not necessary to zone The programmable room thermostat may be a hard the upstairs and downstairs separately, compliance with the zone wired or RF type. requirements can be achieved by a single room thermostat or This diagram is applicable for a hard wired unit or the programmable room thermostat. -
Page 34: Commissioning
▶ In cases where all attempts to find a micro leak have to a static head of 7.5m (24.6ft)). A Schraeder type valve is fitted to failed, Worcester, Bosch Group supports the use of the expansion vessel to allow for pressure adjustment if required. -
Page 35: Starting The Appliance
COMMISSIONING Starting the appliance CAUTION: RUNNING THE APPLIANCE ▶ Never run the appliance when the appliance/system is empty or partially filled. 12 13 Fig. 54 Control panel To reset the boiler, press the reset button (4), the tick symbol will be Key to figure 54 displayed briefly for a successful reset. -
Page 36: Boiler Start Up Screens
COMMISSIONING 6.4.1 Boiler start up screens SCREEN DISPLAY DESCRIPTION On initial start up, the following screens are displayed: All possible screen symbols This screen is displayed briefly 1. All the symbols are displayed for approximately two seconds. during boiler start up and shows 2. -
Page 37: Commissioning
COMMISSIONING Commissioning ▶ Check the gas supply working pressure at the gas valve conforms to values shown in Fig. 58 or Fig. 59 . When running in the service mode, the boiler will operate ▶ Press the button to return to normal operation. both the central heating and the domestic hot water ▶... -
Page 38: Checking The Gas Rate
COMMISSIONING 6.5.2 Checking the gas rate ▶ The gas rate should be measured at the gas meter after the boiler has been operating for a minimum of 10 minutes at maximum output. ▶ See Technical data section on page 9 of this manual for gas rates and CO/CO ratios. -
Page 39: Co And Combustion Checks
▶ The gas valve is factory set and must not be adjusted during commissioning if found to be out of tolerance, please contact the Worcester, Bosch Group help line 0330 123 3366. Zero the analyser Set boiler to ≥... -
Page 40: Finishing Commissioning
COMMISSIONING Finishing commissioning 6.8.1 Replacing the boiler case: 1. Replace the boiler case. 2. Make sure that the securing points on top of the case are properly located. 3. Tighten the bottom two screws (2). Fig. 63 Installing the fascia flap 6.8.4 Installing bottom panel 1. -
Page 41: Hand Over
• The householder may be asked to prove the date of installation, that the boiler was correctly commissioned and, where appropriate, the first year's service has been carried out to the satisfaction of Bosch Thermotechnology Ltd., when requested. These should be documented as a part of the Benchmark Checklist. -
Page 42: Service And Spares
SERVICE AND SPARES Checking flue integrity SERVICE AND SPARES The integrity of the flue system and performance of the boiler can be checked via the flue turret sample points. CAUTION: Mains supplies: Flue gas sample point ▶ Turn off the gas supply and isolate the electrical Air inlet sample point mains supply before starting any work on the appliance and observe all relevant safety... -
Page 43: Component Access
SERVICE AND SPARES Component access Checking the gas inlet pressure To gain access to the components, remove the outer case: NOTICE: Gas inlet pressure 1. Remove the two screws securing the control panel. ▶ Do not continue with the other checks if the correct 2. -
Page 44: Fan Pressure
If the boiler, after completing the above checks, fails the fan pressure sufficient water through the DHW circuit to ensure that test then contact Worcester, Bosch Group for advice. the boiler will not cycle on low heating demands. ▶ After the measurements are taken switch the boiler off. -
Page 45: Cleaning The Heat Exchanger
SERVICE AND SPARES ▶ Set the boiler to minimum power by pressing the down arrow button. Cleaning the heat exchanger – “Min” will flash at the bottom left of the screen. NOTICE: Gaskets and seals – The boiler will take 30 to 35 seconds to ramp down to minimum ▶... -
Page 46: Cleaning The Primary Heat Exchanger
SERVICE AND SPARES 2. Twist the siphon to the left to secure the bayonet connection. 3. Push the black discharge hose, onto the wall frame connector, until fully engaged. 6720803800-03.1Wo Fig. 73 Fitting siphon Fig. 75 Heat exchanger cleaning tool To clean the front channel of the heat exchanger 7.7.2 Cleaning the primary heat exchanger... -
Page 47: Replacement Of Parts
SERVICE AND SPARES Replacement of parts CAUTION: Mains supplies: ▶ Turn off the gas supply and isolate the mains supplies before starting any work on the boiler and observe all relevant safety precautions. CAUTION: Component replacement: ▶ Replace the burner housing gasket and the Flueway sump seal when re-assembling the heat exchanger. -
Page 48: Syphon Removal
SERVICE AND SPARES 7.8.3 Syphon removal 1. Disconnect the discharge hose from the wall frame connector. 2. Rotate the siphon body clockwise to release the bayonet connection. 3. Pull the siphon body down and away from the boiler. Fig. 82 Max safety sensor 7.8.6 Flue overheat thermostat ▶... -
Page 49: Air Pressure Switch
SERVICE AND SPARES 7.8.7 Air Pressure Switch 7.8.8 Auto air vent Ensure that the boiler has been fully drained. NOTICE: Air Pressure Switch 1. Remove the spring clip completely. ▶ Ensure that the tube is reconnected to the Air 2. Lift the air vent out of the housing and remove. Pressure Switch To remove the Air pressure switch assembly: ▶... -
Page 50: Fan Assembly
SERVICE AND SPARES 7.8.10 Fan assembly CAUTION: Component replacement: ▶ After replacement of a gas related component, where a gasket or seal has been disturbed or replaced, check for gas tightness using a gas sniffer/ analyser. ▶ On re-assembly check all affected seals for cracks, hardness and deterioration. -
Page 51: Air/Gas Flap Valve Assembly
SERVICE AND SPARES Combustion air inlet and gas pipe disconnection When refitting the rubber gas pipe, ensure that the pipe 1. Rotate the combustion air inlet pipe anti-clockwise to release from the is correctly oriented by aligning the notch in the pipe fan assembly and pull away from the fan. -
Page 52: Ignition Transformer
SERVICE AND SPARES 7.8.12 Ignition transformer 7.8.14 Burner housing, burner/ gasket To remove the ignition transformer The front two bolts retaining the burner housing are NOT ▶ Isolate the boiler electrically. captive and will drop out when the nuts are removed. ▶... -
Page 53: Heat Exchanger
SERVICE AND SPARES 7.8.15 Heat exchanger Before removal: ▶ Isolate the electrical power to the boiler. ▶ Drain the boiler. Heat exchanger disconnection 1. Undo the flow and return connections. 2. Pull both the flow and return pipes away from the heat exchanger. ▶... -
Page 54: Dhw Temperature Sensor (Ntc)
SERVICE AND SPARES 7.8.17 DHW Temperature sensor (NTC) 7.8.19 Flow sensor, flow restrictor and filter removal ▶ Disconnect the electrical connector from the sensor. ▶ Isolate the cold mains and ensure that the DHW circuit is fully drained. ▶ Unclip the sensor from the pipe. ▶... -
Page 55: Pressure Gauge
SERVICE AND SPARES 7.8.21 Pressure gauge ▶ Ensure that the boiler is fully drained. 1. Carefully prise the lugs apart. 2. Remove the pressure gauge. 3. Withdraw the spring clip from the pressure sensing head housing. 4. Remove the pressure sensing head and pressure gauge capillary from the housing. -
Page 56: Dhw Pressure Relief Valve
SERVICE AND SPARES 7.8.25 DHW pressure relief valve 7.8.27 Hydraulic block removal Before removal: Do not remove the hydraulic block assembly unless absolutely necessary. ▶ Isolate the electrical power to the boiler. Before removal: ▶ Drain the boiler. ▶ Isolate the electrical power to the boiler. ▶... -
Page 57: Access To Boiler Control Components
SERVICE AND SPARES 7.8.29 Access to boiler control components 1. Release the three captive screws retaining the installer access cover. 2. The access cover can now be removed with the flap. Fig. 116 Fuse holder 7.8.30 Replacing the control unit The control unit is supplied in a plastic housing. -
Page 58: Expansion Vessel
SERVICE AND SPARES Removing the control unit ▶ Support the control unit and detach the control unit support strap. 1. Release the two catches underneath the panel. 2. Hinge the control unit up to approximately a 45° angle. 3. Push inwards and upwards to disengage the control unit from the hinge supports. - Page 59 SERVICE AND SPARES Expansion vessel replacement (Boiler fitted) 2. Pull the expansion vessel towards you and down to remove. ▶ Isolate the power from the boiler. ▶ Lower the control panel into the service position. ▶ Isolate the boiler from the heating system using the service valves. ▶...
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Page 60: Short Parts List
SERVICE AND SPARES Short parts list Fan 8 716 117 417 By pass valve 8 716 106 434 0 Gas Valve 8 718 600 04A 0 Control panel 8 737 909 49A 0 Flue overheat thermostat 8 717 206 213 0 Electrodes (including gasket) 8 718 600 28A 0 Burner seal 8 718 600 24A 0 Spark generator... -
Page 61: Fault Finding And Diagnosis
FAULT FINDING AND DIAGNOSIS FAULT FINDING AND DIAGNOSIS Internal wiring diagram Fan wiring: AIR PRESSURE Live = Brown SWITCH Neutral = Blue FLUE STAT SPARK ELECTRODES FLAME SENSE ELECTRODE FLOW MAX SAFETY NTC FLAME SENSE GROUND VALVE SAFETY SOLENOID Blue SAFETY Orange SOLENOID... -
Page 62: Central Heating Function
FAULT FINDING AND DIAGNOSIS Central heating function Fig. 122 Central Heating function CDi Compact - 6 720 813 276 (2015/07) -
Page 63: Preheat And Dhw Function
FAULT FINDING AND DIAGNOSIS Preheat and DHW function Fig. 123 PreHeat and DHW function CDi Compact - 6 720 813 276 (2015/07) -
Page 64: Protection Function
FAULT FINDING AND DIAGNOSIS Protection function Fig. 124 Protection function CDi Compact - 6 720 813 276 (2015/07) -
Page 65: Information And Service Menus
STATUS CODES First Safety timing error During normal boiler operation various Status codes can be displayed by 262 & Internal error call Bosch helpline 0330 123 3366 pressing the button. The first screen of the Information menu displays the current Status... -
Page 66: Selecting The Information Menu
FAULT FINDING AND DIAGNOSIS 2. Use the arrow buttons to scroll through the menu items. Status Fault codes codes ▶ Press the button again to exit the Information menu. Supply sensor exceeded 110°C Start temporarily not allowed due to flow error on CH Too many short burner starts without confirmation of °C reset... -
Page 67: Selecting Service Menus
FAULT FINDING AND DIAGNOSIS 8.5.2 Selecting service menus Maximum temperature This is the current temperature from 1. Press and hold buttons together for one second, the the “Maximum safety sensor”. This display will show Menu 1. sensor is mounted on the front of the heat exchanger. - Page 68 FAULT FINDING AND DIAGNOSIS Para Updated Parameter Description value 2.3C Anti fast cycle flow This sets the temperature drop °C reset °F temperature before the burner re-starts, 6°K Menu 1 hysteresis is the default. This is used in (negative tolerance conjunction with the “Anti fast only) cycle time”...
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Page 69: Reset To Factory Settings
FAULT FINDING AND DIAGNOSIS 8.5.5 Reset to factory settings To reset any or all changes made in menu 2 back to the factory defaults setting: °C reset °F Menu 1 NOTICE: Menu 3 ▶ Any changes made in Menu 3 are not reset via these actions. - Page 70 FAULT FINDING AND DIAGNOSIS Testing the component ▶ Select a component to test. ▶ Press the button, the value 0 will flash. °C reset °F ▶ Use the arrow button to change the value to a flashing 1. Menu 1 ▶...
- Page 71 FAULT FINDING AND DIAGNOSIS °C reset °F °C °F reset °F °C °F °C reset °F Test 1 °C °F Fig. 133 Resetting test Note that it could be up to 10 seconds after the button is Test pressed before the selected component responds. Igniter test.
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Page 72: Fault Codes
FAULT FINDING AND DIAGNOSIS Fault codes Should a fault develop with this boiler (or the system), the boiler will enter a locking or blocking condition, and fault code information will be generated as described in this section. Locking error The boiler display will flash a warning triangle and fault code. At the same time a (static) cause code will also be displayed. Manual intervention is required following clearance of the fault: ▶... - Page 73 Description Reset type Possible cause 237 - 242 - Internal error Call Worcester, Bosch Group Technical helpline 0330 123 3366 Sensor test failed Reset button On power up all safety sensors are checked. Check has failed. Recycle time error...
- Page 76 0330 123 9119 TRAINING: 0330 123 0166 SALES: 0330 123 9669 Worcester, Bosch Group Cotswold Way, Warndon, Worcester WR4 9SW. Tel. 0330 123 9559 Worcester, Bosch Group is a brand name of Bosch Thermotechnology Ltd. worcester-bosch.co.uk 6 720 813 276 (2015/07)
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