Floor standing oil-fired condensing boiler using room sealed flue for fully pumped open vent or sealed central heating systems and domestic hot water cylinders (48 pages)
This appliance is for use with Natural Gas or LPG (Cat II 2H3P). 15SBi GC NUMBER 41 311 43 (N.G.) 24SBi GC NUMBER 41 311 44 (N.G.) 15SBi GC NUMBER 41 311 45 (L.P.G.) 24SBi GC NUMBER 41 311 46 (L.P.G.) APPLIANCE OUTPUTS Natural Gas...
(G20) or 1.1 m /h of propane (G31). 1.4 The installation of the appliance must be in accordance with The 15SBi appliance requires a maximum of 1.78 m /h of the relevant requirements of the Gas Safety Regulations, current natural gas (G20) or 0.68 m...
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2.7 System IMPORTANT: Where back-flow prevention devices, including All dirt must be flushed from the system before connecting the water meters, are fitted the expansion of hot water into cold water main can be prevented. This can result in a pressure appliance.
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NOx CLASSIFICATION FOR BOTH 15 & 24SBi Class 2 SEDBUK Rating 15SBi - Band D - 79.1% 24SBi - Band D - 78.3% Table 6 GAS SUPPLY SYSTEM - BASED ON NG (G20) TOTAL LENGTH OF GAS SUPPLY PIPE (COPPER) metres GAS DISCHARGE RATE - PRESSURE DROP mbar.
Fig. 2. Appliance casing dimensions and 4. Siting The Appliance required clearances. The appliance may be installed in any room subject to the requirements of the current IEE regulations and, in Scotland, the 30mm* relevant electrical provisions of the Building Regulations with 150mm respect to the installation of appliances in rooms containing baths or showers.
The minimum requirements are: Model Position of vent Air from room Air from outside 24SBi High 315cm 158cm 315cm 158cm 15SBi High 315cm 158cm 315cm 158cm Fig. 4. Siting of the flue terminal. TERMINAL POSITION MIN. DISTANCE TERMINAL POSITION MIN. DISTANCE A–...
expansion vessel must be fitted as near to the appliance as 7. Sealed System possible in the return pipe. A filling loop is fitted to the appliance. Refer to Fig 8. 7. Sealed System The system and the appliance must be properly vented. The system must comply with requirements of BS6798 and Repeated venting loses water from the system and usually BS5449.
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Fig. 7. System layout if using twin zone valves (S) plan. IMPORTANT For Details of the wiring requirements Note: INDIRECT for the system A drain cock CYLINDER should be fitted controls, at the lowest please refer to point of the the SBi system heating circuit wiring guide.
The 24SBi appliance requires a maximum of 2.86m /h of natural gas (G20) or 1.1m /h of propane (G31). Refer to Table 1. Bottom Left Hand Side - Facia The 15SBi appliance requires a maximum of 1.76m /h of natural Earth 230V gas (G20) or 0.68m /h of propane (G31).
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Fig.13 . Wiring diagram - pictorial. Overheat Cut-off CH Sensor Flame Sense Spark Electrode Electrode Gas Valve Position Air Flow Valve Switch Pump Y Plan (Optional) Cylinder Thermostat Control Board Facia Mounted Timer (Optional) 2 green 2 red bl - Blue br - Brown y - Yellow 2 orange...
Cut the flue duct hole at 110mm diameter [150mm diameter for 11. Installing The Appliance internally fitted flues]. 11.4 Wall Mounting Plate and Manifold Note: READ THIS SECTION FULLY BEFORE COMMENCING THE Fit the plugs and fix the mounting plate and manifold assembly INSTALLATION to the wall.
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Fig. 21 screws (2) 24SBi - 75mm Horizontal flue up to 1m - 75mm Vertical flue up to 1m 15SBi - 74mm Horizontal flue up to 1m - 79mm Vertical flue up to 1m Connections cover fixing...
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Automatic air Fixing screw vent Terminal assembly Appliance casing Telescopic adjustment Restrictor Ring Sizes 24SBi - 75mm horizontal and vertical flue up to 1m 15SBi - 74mm horizontal flue up to 1m 15SBi - 79mm vertical flue up to 1m...
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Fig.23 . Extension Duct. Turret assembly Terminal Fixing screws Fixing screw assembly Ducts of equal length Appliance casing Shorten first extension fitted to the turret assembly if more than one extension is fitted Fig.25 . Rear flue. Fig.24. Flue duct length (side flue). Terminal assembly Flue...
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Fig.26 . Flue Turret Fixing . Fig.27 . Terminal assembly for internal fitting of the flue. 4. Rubber sealing gasket 1. Flue centering ring 1. Flue turret assembly 5. Flue Terminal 2. Air duct 2. Clamp 3. Flue duct 3. Appliance 4.
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Fig. 29 - Elbow to Flue Turret Fig. 31 - Facia Connections Cover. 120mm Assembly. 100mm Flue Turret Bend 1. Control Panel Fixing Screws Fig.30 Vertical Adapter. 2. Facia 3. Control Panel Pivot Point Flue Duct 4. Connection Cover 5. Connection Cover Fixing Screws Air Duct Fig.32.
Fig 34 - Programmer Connection - Facia Position 1. Programmer 4. Programmer 2. Programmer Connector Fixing Clip 3. Pressure Gauge Fig. 36. Pump venting. 12. Commissioning The Appliance 12.1 Lift off the cabinet front panel. . Check that the electricity and gas supplies to the appliance are turned off and that all the water connections throughout the system are tight.
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90 litres. Refer to BS7074 Part 1, BS5449 and Table 9. If the system volume is greater then an extra vessel must be fitted as close as possible to the appliance in the central 15SBi heating return connection and pressurised to the same figure as the integral vessel.
Inner Casing. Unscrew the four screws and remove. Refer to Fig 18. 13. Instructions To The User Combustion Chamber. Unscrew the two screws at the top. Loosen but do not remove the two wing-nut extended screws at the sides, unhook the clips and remove the chamber. Refer to Fig 41 Fig.40 .
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Fig. 42. Inner Casing 24SBi Fan Assembly Air Flow Sensing Tubes Flue Hood Overheat Thermostat Combustion Chamber Combustion Chamber Fixing Screws Gas Pipe (Burner Assembly) Burner Assembly Spark Electrode Assembly 10. Flow Pipe 11. Flow Sensor 12. Heat Exchanger 13. Auto Air Vent 14.
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Fig.43 . Lower Casing - Gas and Water Controls. 1. Pump 2. Flow manifold 3. Filling Loop 4. Air pressure switch 5. Gas Valve 6. Pressure relief valve 7. Connector 8. Bypass 15.4.1 Gas Valve Do not remove the inner casing. Fig.44 .
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15.4.5 Combustion Chamber Insulation Remove the burner and the primary heat exchanger. Refer to Fig.46. Pressure Gauge Fixing. Section 15.3.4, 15.4.21. Replace the side and front pads in the combustion chamber assembly. Replace the rear insulation pad. Refer to Fig.45 Fig.45.
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Fig.48. Rear Control Board Cover. 1. Control Board Cover Fixing Screws (4) 2. Rear Connections Cover Fixing Screws (2) 3. Rear Connections Cover 4. Control Board Cover 5. Facia 6. Pressure gauge 7. clock clips 15.4.9 Control Board 15.4.11 Heat Exchanger Remove the facia bottom panel and carefully disconnect all the Drain the appliance as described in Section 15.3 preceding.
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15.4.15 Air Flow Detector Remove the fan as described in 15.3.13. Unscrew and withdraw, Fig.51. Fan /Flue Hood Assembly through the fan outlet, the air flow detector. Refer to Fig .51. The detector is 'handed' - do not force it into place. 15.4.16 Primary Flow Sensor Carefully pull-off the connections.
18. Fault Finding NOTE: This fault finding information is for guidance only. Worcester Heat systems cannot be held responsible for costs incurred by persons not deemed to be competent. To use this guide, operate the boiler and follow the observations down the left hand column until the boiler fails. The associated tests will help find the fault.
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BOILER DEMAND TEST Set the system to create a boiler demand. Turn facia control knob to maximum. Does the boiler pump run? Is the facia Refer to (removal of pump indicator above section venter plug may help still on? identify rotation of pump) Drop down the facia and expose the three...
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Remove electrical Does the Pressure switch Does the electrode Replace tubes. connectors from the fan stop has not closed. spark at the burner? If condensation has pressure switch and after a few Are the silicone occurred also replace restart the boiler. Is seconds? tubes in good pressure switch and...
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Are the spark electrodes and gap Repair or replace connections in electrodes or leads. good order? Replace control board. (Section 15.4.9) (LOCKOUT will occur Does the burner Rectify gas supply after 8 seconds) ignite? (use spy glass problem. Is gas supply to observe flame) connected and at the correct pressure?
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Set the system to Drop down the facia System is still creating a demand. end the boiler and expose the three Check appropriate “IMPORTANT NOTES” section demand. PCB rear of the wiring guide booklet. If this does not Does the burner connections.
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This manual is to be used in conjunction with the variant part number of the bar code below: Bosch Group Worcester Heat Systems Limited, Cotswold Way, Warndon, Worcester WR4 9SW. Telephone: 01905 754624. Fax: 01905 754619. Technical Helpline 08705 266241.