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23

8.6

ELECTRODES (Alpha 240XE only) - Fig. 20

Gain access as in section 8.1.

1.

Remove the five screws securing the combustion chamber front cover and remove the cover.

2.

Disconnect the leads from the electrodes.

3.

Withdraw the main burner out of the boiler. Take care not to damage the side insulation panels.

4.

Flame sensing electrode
Remove the screw securing the electrode and withdraw the electrode.
Fit the new electrode, ensuring it is positioned correctly (see Fig. 20).

5.

Ignition electrodes
Remove the screws securing the electrodes and withdraw the electrodes.
Fit the new electrodes, ensuring they are positioned correctly and the spark gap is correct (see Fig. 20).

Re-assemble

1.

Replace the burner, ensuring it is located correctly over the injectors and the four locating pins (two each side).

2.

Replace the combustion chamber front cover, ensuring the bottom is correctly located in the burner.

3.

Complete re-assembly as described in Routine Servicing, section 7.4 paragraphs 4 to 9.

Alpha 240XP and 240XE - Component Replacement

8.7

MAIN BURNER

1.

Remove the burner as described in Routine Servicing, section 7.2.

2.

Re-assemble with a new burner as described in Routine Servicing, section 7.4.

8.8

BURNER INJECTORS

1.

Remove the burner as described in Routine Servicing, section 7.2.

2.

Unscrew the damaged injector and screw in a replacement.

3.

Re-assemble as described in Routine Servicing, section 7.4.

Securing

screws

Flame sensing electrode

11 to 12 mm

3 to 3.5 mm

9 to 10 mm

Ignition electrodes

Fig. 20

Summary of Contents for Alpha 240XE

Page 1: ...ired Combination Boilers Alpha 240XP G C No 47 532 10 Alpha 240XE G C No 47 532 11 Service Listed 0051 For use with Natural Gas only Leave these instructions with the User Nepicar House London Road Wrotham Heath Sevenoaks Kent TN15 7RS For Technical help or for Service call ALPHA HELPLINE Tel 0870 3001964 ...

Page 2: ... with the following recommendations Gas Safety Installation and Use Regulations All relevant Building Regulations issued by the Department of the Environment Building Standards Scotland Consolidation Regulations issued by the Scottish Development Department Local Water Bye Laws Health Safety Document No 635 The Electricity At Work Regulations 1989 The installation should also be in accordance with...

Page 3: ... Max System Pressure Min System Pressure Max System temperature Pressure Relief Valve Setting Expansion Vessel Size pre charge press Flow Connection Return Connection Relief Valve Connection Recommended System Pressure cold CH Water Temp Approx max C F 3 bar 0 5 bar 82 C 3 bar 44 PSI 8 L at 0 8 bar 22 mm 22 mm 15 mm 1 0 bar 82 180 Domestic Hot Water Max Mains Inlet Water Pressure Min Mains Water P...

Page 4: ...45 Bend is equivalent to 0 5 m of flue length The Vertical Flue terminal assembly is equivalent to 1 m of flue length 2 8 AVAILABLE PUMP HEAD FOR CENTRAL HEATING gal min 3 32 2 78 2 32 1 85 1 47 Btu h 79 500 60 000 50 000 40 000 31 700 kW 23 3 17 58 14 65 11 63 9 3 metres 2 33 3 00 3 45 3 85 4 20 feet 7 7 9 8 11 3 12 6 13 8 Output Available pump head metres 2 95 3 45 3 75 4 05 4 35 feet 9 7 11 3 1...

Page 5: ...itch 14 Primary flow valve microswitch 15 Pump and air separator 16 Automatic air vent 17 DHW temperature sensor 18 Primary temperature sensor 19 Overheat thermostat 20 Expansion vessel 21 Gas valve 22 Main burner injector 23 Main burner 24 Pilot burner 25 Thermocouple 26 Main heat exchanger 27 Flue hood 28 Fan 29 Air pressure switch 30 Positive pressure point 31 Negative pressure point 32 Flue ad...

Page 6: ...rimary flow valve microswitch 15 Pump and air separator 16 Automatic air vent 17 DHW temperature sensor 18 Primary temperature sensor 19 Overheat thermostat 20 Expansion vessel 21 Gas valve 22 Main burner injector 23 Main burner 24 Ignition electrodes 25 Flame sensing electrode 26 Main heat exchanger 27 Flue hood 28 Fan 29 Air pressure switch 30 Positive pressure point 31 Negative pressure point 3...

Page 7: ...rtment used to enclose the boiler must be designed and constructed specifically for the purpose i e comply with the Building Regulations 3 4 FLUE SYSTEM Fig 4 The flue system must be installed in accordance with BS 5440 1 The flue assembly supplied for the boiler is 0 75 m in length For horizontal flues ensure there is a slight downward slope towards the terminal Additional flue components are ava...

Page 8: ...40XE General Boiler Information L B C 185 mm C B E C B E B F B C L B E F 185 mm 90 bend 1 metre L B C 185 mm 2 x 45 bends 1 metre VERTICAL FLUE OPTIONS Fig 4 Not less than 300 mm Not less than 450 mm H H Not less than 450 mm Not less than 300 mm Hmax 4 metres Hmax 3 metres ...

Page 9: ...ted surface If the terminal is fitted less than 2 m above a surface to which people have access the terminal must be protected by a terminal guard A suitable guard type K3 G C No 393 554 is available from Tower Flue Components Ltd Vale Rise Tonbridge Kent TN9 1TB 3 6 BOILER LOCATION The boiler is not suitable for external installation The boiler must be installed on a flat vertical wall which is c...

Page 10: ...Fig 6 of 10 2 metres of water Provision should be made to replace water lost from the system This can be by manual or automatic means as shown in Figs 7 and 8 The position for connecting an automatic make up vessel is indicated in Fig 6 A double check valve assembly must be used as shown in Fig 8 Filling of the system must be carried out in a manner approved by the local Water Undertaking Where al...

Page 11: ... All taps and mixing valves used with the hot water system must be suitable for operating at a mains pressure of up to 8 bar Showers A shower may be used with the boiler if required If a loose or flexible head type shower is used it may require the fitting of a double check valve to comply with Water Bye Law 17 Bidets No anti syphonage arrangements are necessary provided the outlets are shrouded a...

Page 12: ...ixing holes Template Rear exit hole 110 mm dia Boiler outline Top fixing holes Ensure line is level 190 mm 135 mm 4 4 FIT THE BOILER Refer to Fig 10 1 Lift the boiler and locate it on the mounting bracket or the top fixing screws when piping from above 2 Adjust the position of the boiler as necessary Fit the bottom screws to secure the boiler in position do not forget to tighten the top screws whe...

Page 13: ...er ducts to length Note Do not cut the outer duct end with the two holes these are for securing the terminal Ensure that all cuts are square and burr free 7 Fit the flue terminal to the outer duct by inserting it into the end with two holes Align the holes and secure with the two screws provided 8 Place the inner flue duct back into the outer duct 9 Pass the flue assembly through the wall from ins...

Page 14: ...all thickness 110 mm Inner flue duct length finished wall thickness 147 mm Side flue Outer air duct length finished wall thickness the distance from the inside wall to the side of the boiler 145 mm Inner flue duct length finished wall thickness the distance from the inside wall to the side of the boiler 182 mm 5 When measuring the outer duct measure from the end of the tube as shown in Figs 12 and...

Page 15: ...move the link between terminals 1 and 2 Pass the cable through the cable clamp through the grommet cut as necessary and connect it to terminals 1 and 2 Replace the terminal block cover Refer to section 2 9 4 Replace the terminal block ensuring it is located correctly on the plastic pins and replace the cover 5 Ensure that there is sufficient free cable to allow the control panel to be raised and l...

Page 16: ...and allow water to flow until no air is present Turn off taps 5 2 BOILER CONTROLS Fig 16 5 COMMISSIONING Alpha 240XP and 240XE Commissioning Fig 16 Alpha 240XP Alpha 240XE Gas Control GAS OFF System Pressure Gauge Central Heating Thermostat Domestic Hot Water Thermostat Selector Switch Pilot and Burner Viewing Window 0 THERMOSTAT 0 THERMOSTAT SELECTOR bar 0 4 3 2 1 Clock if fitted OCEAN 240XP HELP...

Page 17: ...an be viewed through the window in the room sealed chamber panel When the gas control is released the fan goes to slow speed 6 Open a hot water tap the main burner will light and the boiler will provide hot water Close the tap and the burner will go out 7 Set the selector switch to CH and DHW The boiler will now run in the central heating mode The pump will start the fan will start once the pressu...

Page 18: ...s 7 Explain to the User that an internal frost thermostat is fitted in the boiler and that elecrical supply to the boiler must be left on and for the Alpha 240XP boiler the pilot is alight for the thermostat to operate 8 Show the User the position of the pressure relief valve discharge pipe 9 Hand the User s instructions to the User 10 Leave these Installation and Servicing instructions with the U...

Page 19: ...o reset it Alpha 240XP and 240XE Boiler Operation Routine Servicing To ensure efficient operation of the boiler it is recommended that it is checked and serviced as necessary at regular intervals The frequency of servicing will depend upon the particular installation conditions and usage but in general once per year should be adequate It is the law that any service work must be carried out by a co...

Page 20: ...er insulation panels Any damaged panels must be replaced Refer to Component Replacement section 8 23 3 Check the condition of the burner injectors on the manifold carefully clean them with a soft brush if necessary Do not use a brush with metallic bristles as this might damage the injectors 4 Remove any fallen deposits from the bottom of the inner case 5 Unscrew and replace any injector that appea...

Page 21: ...nal settings The replacement of components in sections 8 3 to 8 21 does not require draining of the boiler 8 1 GENERAL ACCESS Fig 17 Ensure the electrical supply is isolated and the gas supply is off Remove the two screws securing the top of the front casing Lift the cover up slightly and remove 1 If access is required behind the control panel Remove the two fixing screws one each side securing th...

Page 22: ...at connection is in position in the gas valve before securing the thermocouple 2 Light the boiler and test the pilot supply for gas soundness Refer to Commissioning section 5 4 3 Complete re assembly as described in Routine Servicing section 7 4 paragraphs 5 to 9 Alpha 240XP and 240XE Component Replacement Pilot burner Thermocouple Electrode Pilot injector Pilot shield 5 mm Spark gap Fig 19 8 4 IG...

Page 23: ...orrect see Fig 20 Re assemble 1 Replace the burner ensuring it is located correctly over the injectors and the four locating pins two each side 2 Replace the combustion chamber front cover ensuring the bottom is correctly located in the burner 3 Complete re assembly as described in Routine Servicing section 7 4 paragraphs 4 to 9 Alpha 240XP and 240XE Component Replacement 8 7 MAIN BURNER 1 Remove ...

Page 24: ...CH Fig 22 1 Gain access as in section 8 1 remove the five screws securing the combustion chamber front cover and remove the cover 2 Disconnect the pressure sensing tubes 3 Remove the two fixing screws and disconnect the wiring 4 Connect the wiring to the new switch black to C brown to NC blue to NO and reconnect the pressure tubes see Fig 22 5 Secure the new switch in position 6 Re assemble in rev...

Page 25: ... section 8 1 2 Disconnect the coil wires and pressure tube from the gas valve 3 Loosen the two screws see Fig 25 securing the solenoid plug and disconnect the plug 4 Remove the four manifold screws from beneath the boiler 5 Disconnect the burner manifold union underneath the room sealed chamber 6 Carefully push the manifold towards the rear of the boiler take care not to damage the manifold sealin...

Page 26: ...a replacement ensuring that the holder snaps into position 3 Re assemble in reverse order ensuring the terminal block is located correctly on the plastic pin 8 18 IGNITION PCB Alpha 240XE only Refer to Fig 27 1 Gain access as described in section 8 1 2 Disconnect the wiring connectors then remove the four fixing screws 3 Connect the wiring to the new PCB and re assemble in reverse order 8 19 RELAY...

Page 27: ... two fixing screws and disconnect the wiring 3 Refer to Fig 28 connect the wiring to the new PCB and re assemble in reverse order Alpha 240XP and 240XE Component Replacement Fig 28 Alpha 240XP Fig 27 Alpha 240XE Ignition electrode leads Relay PCB Ignition PCB Reset switch Relay PCB Ignition PCB Ignition lead ...

Page 28: ...CHES Fig 31 Note that both switches are the same 1 Gain access as described in section 8 1 2 Remove the screw securing the switch bracket to the diverter valve disconnect the wiring and remove Re assemble in reverse order with a new switch Ensure that the bracket is located under the nut flange 3 Connect the wiring as follows PRIMARY flow switch back of diverter valve red wires to terminals as sho...

Page 29: ...R INSULATION 1 Gain access as described in section 8 1 2 Side and front panels slide out 3 To replace the rear panel remove the heat exchanger as described in section 8 26 and slide out the side insulation panels Prise out the top of the rear insulation panel and lift it up and out of the boiler 4 Fit a new panel and re assemble in reverse order Alpha 240XE Connect the fan wiring blue to terminal ...

Page 30: ... the wiring 2 Connect the wiring to the new head as follows Brown to L Blue to N Green yellow to Ensure the pump is set to maximum 3 and re assemble in reverse order 3 Refill and pressurise the system Refer to Commissioning section 5 1 Complete pump 1 Unscrew the automatic air vent from the pump outlet 2 Disconnect the pump unions and withdraw the pump remove the wiring cover and disconnect the wi...

Page 31: ...on and that the by pass retaining clips are correctly fitted and locate in the slots 9 Refill and pressurise the system Refer to Commissioning section 5 1 Alpha 240XP and 240XE Component Replacement DHW heat exchanger DHW heat exchanger securing screws DHW expansion device connection Drain tap Pressure relief valve Fig 34 Fig 35 8 34 DRAIN TAP Fig 35 1 Drain the boiler heating circuit as described...

Page 32: ...connections from the diverter valve Two flow sensing pipes pressure gauge sensor expansion vessel connection release the other end to allow the pipe to be moved out of the way CH flow pipe small by pass pipe CH flow isolating valve 5 Remove the clips accessible from under the boiler retaining the by pass pipe to the manifold and diverter valve and withdraw the pipe 6 Remove the screw securing the ...

Page 33: ...tem Refer to Commissioning section 5 1 8 41 EXPANSION VESSEL 1 Drain the boiler heating circuit as described in section 8 2 2 Disconnect the pipe from the diverter valve and expansion vessel 3 Remove the nut and washer securing the expansion vessel to the boiler and lift the vessel out of the boiler 4 When replacing the vessel ensure that the connection is towards the front of the boiler and re as...

Page 34: ...34 Alpha 240XP and 240XE Wiring Diagrams 9 WIRING DIAGRAMS 9 1 ILLUSTRATED WIRING DIAGRAM Alpha 240XP ...

Page 35: ...35 Alpha 240XP and 240XE Wiring Diagrams 9 2 ILLUSTRATED WIRING DIAGRAM Alpha 240XE ...

Page 36: ...36 Alpha 240XP and 240XE Wiring Diagrams 9 3 FUNCTIONAL FLOW WIRING DIAGRAM Alpha 240XP ...

Page 37: ...37 Alpha 240XP and 240XE Wiring Diagrams 9 4 FUNCTIONAL FLOW WIRING DIAGRAM Alpha 240XE ...

Page 38: ...ring Replace ignition microswitch assy Replace thermocouple Replace overheat thermostat Turn selector to Connections OK Continuity across ignition microswitch and Ign PCB M1 connector between terminals 1 2 Fan connections correct at fan and main PCB Is approx 440 V across terminals 17 19 Main PCB Is 240 V across terminals 7 12 and at Ign PCB M2 connector terminals 3 4 Ign PCB M2 connector is 240 V...

Page 39: ... YES Go to section page 41 D Go to section page 42 J Air pressure switch proved NO Go to section page 41 E Burner output modulates to maintain temperature set at thermostat NO NO YES Clean DHW temp sensor and DHW heat exchanger Reduce DHW flow rate from 10 to 5 L min Burner modulates NO Close DHW tap YES DHW flow valve senses no flow Primary water diverted to CH system DHW flow switch released off...

Page 40: ...d NO YES Go to section page 41 D Go to section page 42 J Air pressure switch proved Spark at ignition electrodes for upto 10 seconds Go to section page 42 L YES NO NO YES 240XE YES 240XP YES Go to section page 41 E Press red button to reset NO YES 240XE only Burner lights YES Go to section page 41 F Go to section page 42 I Burner output modulates until set temperature is reached Burner goes out NO...

Page 41: ... PCB terminals 39 40 Replace microswitch 1 YES YES YES NO NO DHW Primary temp sensor faulty Cold resistance approx 11 k ohms resistance reduces with increase in temp Replace sensor 2 3 240XE Fan connections correct at fan and PCB 240XP Fan connections correct at fan and PCB Is 240 V across PCB terminals 16 19 Is approx 440 V across PCB terminals 17 19 Fan jammed or faulty winding i e correct cold ...

Page 42: ... ignition PCB YES NO YES Check and correct 1 Ignition electrodes and leads 2 Electrode connections 3 Spark gap and position H Is 240V at Main PCB across terminals 5 7 and at Ignition PCB M1 connector across terminals A C Air pressure switch proved YES YES Replace ignition PCB Replace main PCB NO NO Go to section page 41 E Replace main PCB NO YES 240V at internal clock terminals 1 and 2 20V DC acro...

Page 43: ...rode Ignition Left Electrode Flame sensing Electrode lead Ignition Expansion vessel 8 Litre Pressure relief valve 3 bar Insulation panel set combustion chamber Automatic air vent and seals Relay PCB Pressure gauge Drain tap Pilot injector 0 27 mm Pilot tube Thermocouple Electrode Electrode lead Ignition PCB Ignition microswitch and cable Description British Gas GC No 343 723 343 557 385 830 343 55...

Page 44: ...blications 2000 Tel 01670 356525 07 97 D85 Part No 920 284 1 These instructions have been carefully prepared but we reserve the right to alter the specification at any time in the interest of product improvement Alpha Therm Limited 1997 e c i v r e S f o s l i a t e D e c i v r e S f o e t a D Service Engineer Alpha Therm Limited Nepicar House London Road Wrotham Heath Sevenoaks Kent TN15 7RS emai...

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