SERVICING INSTRUCTIONS This appliance is for use with Natural Gas or LPG (Cat II 2H3P). 9/14CBi GC NUMBER 41 311 50 (N.G.) 14/19CBi GC NUMBER 41 311 52 (N.G.) 19/24CBi GC NUMBER 41 311 54 (N.G.) APPLIANCE OUTPUTS 9/14CBi N.G.
2.1 General Information The Worcester boilers provide a heat output of between 9-14kW (9/14CBi), 14-19kW (14/19CBi) & 19-24kW (19/24 CBi) factory set at mid-range and contain a temperature control and all the appropriate safety controls. They are suitable for fully pumped open vent or sealed systems.
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A vertical flue option is also available with flue lengths from 1.1m (without cutting) to a maximum of 3.35m (19/24CBi) or 4.1m (9/14 and 14/19CBi). Optional 45° and 90° bends are available with this option. NOTE: When using flue bends the flue length is reduced (see Section11.2.8).
EXTERNAL FIX INTERNAL FIX MINIMUM LENGTH MAXIMUM LENGTH MAXIMUM LENGTH MINIMUM LENGTH MAXIMUM LENGTH MINIMUM LENGTH MAXIMUM LENGTH INCLUDING TERMINAL 3.35m (19/24CBi) or 4.1m (9/14 and 14/19CBi) Table 3 14/19CBi FLOW/RETURN BOILER OUTPUT RESISTANCE MIN. FLOW RATE DIFFERENTIAL °C 11.7 18.2 19 .05...
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14/19 & 19/24CBi 33.5kg 9/14CBi 41kg 14/19 & 19/24CBi 47kg PERFORMANCE SPECIFICATIONS (Sealed System) 9/14CBi 9.0 - 14.0kw 14/19CBi 14.0 - 19.05kw 19/24CBi 19.05 - 23.45kw 9/14CBi NG 78.5 D 9/14CBi LPG 81.0 D PIPE DIAMETER mm PIPE DIAMETER mm —...
4. Siting The Appliance Fig. 3. Appliance pipework connections The appliance may be installed in any room subject to the 165mm requirements of the current IEE regulations and, in Scotland, the FLOW relevant electrical provisions of the Building Regulations with RETURN respect to the installation of appliances in rooms containing baths or showers.
The minimum requirements are: Model 19/24CBi 14/19CBi 9/14CBi If the boiler is fitted between kitchen units and a decorative door panel is fitted then the top and bottom of the space must be left open. MIN. DISTANCE TERMINAL POSITION I–...
A by-pass is required if the controls i.e. 2-port valves, can result in the closure of the CH and DHW circuits when the boiler is hot. If mechanically operated thermostatically controlled valves are fitted on all radiators then a by-pass located at least 2m from the boiler is required.
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Fig. 6. System layout if using Honeywell 'S' plan Feed and Vent Cistern Heating vent (22mm min.) Boiler 150mm max Fig. 7. Fully pumped sealed system. Note: A drain cock should be fitted at the lowest point of the heating circuit...
The 19/24CBi appliance requires a maximum of 2.72 m natural gas (G20), 1.05 m /h propane (G31). The 14/19CBi appliance requires a maximum of 2.18 m natural gas (G20), 0.84 m /h propane (G31). The 9/14CBi appliance requires a maximum of 1.62 m natural gas (G20), 0.63 m...
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Fig.10. Boiler wiring diagram Air pressure switch white grey brown Overheat Thermostat orange black Temperature sensor Gas Valve earth Pump Neutral Installer Connections Permanent Neutral Permanent Live Switched Live (Boiler Demand) Spark Electrode blue brown Pump Live Polarity of these connections is not important.
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(5A Fuse) Common isolator for wiring centre and boiler Should be located adjacent to the boiler OUTSIDE OF BOILER INSIDE OF BOILER Cable clamp Earth post System components wired into terminal strip in accordance with component manufacturers instructions Boiler/pump demand from...
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Fig. 12a. Boiler Assembly 9/14CBi Shown set for Rear Only flue kit 1. Inner case 2. J bolts and wing nuts (2) 3. Combustion chamber cover 4. Burner 5. Burner fixing screw 6. Control knob 7. Indicator lights 8. Base/controls fixing screw 9.
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Fig. 12b. Boiler Assembly 14/19 and 19/24CBi Shown set for 1. Inner case 2. J bolts and wing nuts (2) 3. Combustion chamber cover 4. Burner 5. Burner fixing screw 6. Control knob 7. Indicator lights 8. Base/controls fixing screw 9.
To install a boiler with a telescopic horizontal flue kit refer to Section 11.2. To install a boiler with a vertical flue refer to Section 11.2. and the literature with the flue kit. 11. Installation of the Boiler with a Rear Only Flue Kit 11.1 Unpacking the Boiler...
(iii) (iv) Lift the boiler onto the wall mounting plate. See Fig. 15. Level the boiler using the two levelling feet at the base of the back panel. Fit the bottom fixing screw (or optional security screw). Connect the gas supply using the nut and olive supplied in the literature pack - details of the position are shown in Fig.
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Fig. 15 . Fixing the appliance to the wall mounting plate. 1. Telescopic flue assembly 2. Wall mounting plate 3. Fixing or security screw 4. Levelling feet (2) 5. Restrictor plate with rectangular hole 6. Gasket 7. Flue fixing screws 8.
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Check the contents against the packing list. Remove the wall mounting template, the mounting plate assembly and the flue spigot and restrictors. The flue spigot is positioned within the boiler carton and not in the accessory pack. 11.2.2 Site Preparation...
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Refer to Fig. 17. If the length needed is greater than 725mm then extension duct kit/s will be required - each kit extends the flue by 750mm up to a maximum of 2.5m (19/24CBi) or 3.0m (9/14 and 14/19CBi). See table below. EXTENSION (iv) Measure length L.
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11.2.6 Telescopic Horizontal Flue Kit up to 750mm in Length The standard flue can be telescopically adjusted to any length between 425mm and 725mm. It will only be necessary to cut the standard assembly if L<425mm. Cut the flue turret assembly and the terminal assembly by the same amount i.e L=350 - remove 75mm from each assembly.
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Flue terminal Clamping ring Lift the boiler onto the wall mounting plate. See Fig. 27. Level the boiler using the two levelling feet at the base of the back panel. Fit the bottom fixing screw (or optional security screw). Connect the gas supply using the nut and olive supplied in the literature pack - details of the position are shown in Fig.
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Both of these hoses should be discarded. Refer to Fig. 16. Slide the flue hood only back into the boiler facing the opposite way to before. Ensure that the flue hood hits the stops at the rear and the rear combustion chamber slots in underneath (see Fig.
Failure to comply with these recommendations, may invalidate the boiler warranty. If any of the above is unclear, then please contact The Worcester Technical Services for further advice. 12.1 Remove the outer casing by first loosening the base screw.
Operate the appliance and take note of any irregularities. Refer to Section 18-Fault Finding. Check the combustion performance Lift off the cap from the sample point on the top of the boiler and connect the meter. Refer to Fig 30/30a. With the appliance at maximum rate and stable expect readings...
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Fan - Horizontal Flue. Remove the combustion chamber cover. Carefully pull off the electrical connections and the tubes from the air flow detector. Loosen the two clamps to remove the fan . Refer to Fig 34. Flue Hood - Horizontal Flue. Remove the fan, see above.
15. Replacement Of Parts Important: Turn off the gas and electricity supplies and drain, where necessary, before replacing any components. 15.1 Always check for gas soundness where relevant and carry out functional checks as described in Section 12 Commissioning. Any O-ring, gasket or seal that appears damaged must be replaced.
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Fig. 34 . Inner Casing - Gas and Electric Controls. 9/14CBi shown. Fig. 35 . Base/Control Board Assembly 1. Inner casing 2. J bolts and wing nuts (2) 3. Combustion chamber cover 4. Burner assembly 5. Inner case cover fixing points (4) 6.
15.4.1 Gas Valve NOTE: If the left hand clearance is >50mm then the gas valve can be replaced with the burner and combustion chamber cover in place by unscrewing the four extended screws at the manifold on the outside of the inner casing. The manifold gasket should be replaced if it is damaged or has deteriorated.
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15.4.5 Control Board Lower the base plate/control assembly and carefully disconnect the plug-in connector and all the electrical connections. Refer to Fig. 35. Release the five clips and lift out the control board. Refer to Fig. 35. Pull out and replace, if necessary, a failed fuse. Fig.
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15.4.7 Air Flow Sensor Remove the fan as described in 14.3. Unscrew and withdraw, through the fan outlet, the air flow sensor. Refer to Fig .38 and 38a. The detector is 'handed' - do not force it into place. Fig. 38 - 9/14CBi Fig.
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Remove the side insulation pads. Unscrew the combustion chamber rear panel and lower. Cut the rear insulation board to remove it from the boiler. Cut the replacement board approximately 90mm from the top so that the joint will be behind the heat exchanger.
Adjust the burner setting pressure as required. Refer to Table 1 and Fig. 31. (XII) Fix the Red Arrow on the data plate to show the boiler setting. If the setting has been altered the adjustment screw should be resealed by a dab of paint to stop un- authorized adjustment.
NOTE: This fault finding information is for guidance only. Worcester, Bosch Group cannot be held responsible for costs incurred by persons not deemed to be competent. The electronic control for this boiler incorporates three lights: Boiler demand, flame on and lockout. These form the basis for this fault finding guide.
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Is there 230V at connector X1 between pins SL & N? Replace control board. NOTE: It is normal to see only a demand light if the boiler is hot and the burner has temporarily shut off. Ensure boiler is cool and user control set to maximum.
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Is the boiler in a very cold environment i.e is the primary water temperature below 5°C? Boiler is running in 'Autofroststat' mode. Is the system fully water pressurised and is all air vented? The system should have a bypass fitted as described in Section 7.
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Are the electrodes and gap and cover. connections in good order? Replace control board. flame sense or cable to it. NOTE: Do not attempt to light the boiler with the combustion chamber cover removed. Repair or replace spark electrode or HT leads.
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Delivered primary water Check thermister Move control knob to lower temperature always too hot. sensor/heat conductive Replace control board. setting. (Over 85°C) paste. Such a fault is likely to be caused by one or more of the following: Low gas pressure Delivered primary water temperature appears too Partially blocked flue...
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THERMOSTATIC RADIATOR VALVES AUTOMATIC BYPASS TO SYSTEM FOR ALL BOILERS CONFIRM THE FOLLOWING THE SYSTEM HAS BEEN FLUSHED IN ACCORDANCE WITH THE BOILER MANUFACTURER S INSTRUCTIONS? THE SYSTEM CLEANER USED THE INHIBITOR USED FOR THE CENTRAL HEATING MODE, MEASURE & RECORD...
SERVICE INTERVAL RECORD I t i s r e c o m m e n d e d t h a t y o u r h e a t i n g s y s t e m i s s e r v i c e d r e g u l a r l y a n d t h a t y o u c o m p l e t e t h e a p p r o p r i a t e S e r v i c e I n t e r v a l R e c o r d B e l o w.
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This manual is to be used in conjunction with the variant part number of the bar code below: www.worcester-bosch.co.uk Bosch Group Worcester, Bosch Group, Cotswold Way, Warndon, Worcester WR4 9SW. Telephone: 01905 754624. Fax: 01905 753130. Technical Helpline 08705 266241. Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Limited.