Saunier Duval SYLVA FF 24 E Servicing Instructions

SYLVA 01773 828100 IN WARRANTY TECHNICAL HELPLINE 01773 828400

«Introduction» section page 3 of the Installation and User instructions for a description of the basic functions of the boiler. The «Users» section describes how to safely operate the boiler. CONTENTS Routine cleaning and inspection .................................. Page 4 - 5 Replacement of parts ............................................................... 6 - 9 Domestic hot water thermostat .................................................... 6 Fan .................................................................................................... 6 Air pressure switch .......................................................................... 6 Printed circuit board ...................................................................... 6 Central heating thermistor ............................................................ 6 Central heating temperature control .......................................... 6 Pump ........................................................................................... 6 - 7 Temperature gauge ....................................................................... 7 Pressure gauge ............................................................................... 7 3-way valve head .......................................................................... 7 3-way valve ..................................................................................... 7 Loss of water switch ........................................................................ 7 Gas valve module .......................................................................... 7 Gas valve.................................................................................... 7 - 8 Modulating coil ............................................................................... 8 Central heating safety valve ........................................................ 8 Temperature/pressure relief valve ................................................ 8 Anode .............................................................................................. 8 Heat exchanger ............................................................................. 8 Expansion valve .............................................................................. 8 Central heating expansion vessel ................................................ 9 Domestic expansion vessel ........................................................... 9 High limit thermostat ...................................................................... 9 Combustion chamber insulation .................................................. 9 Burner ............................................................................................... 9 Burner injectors................................................................................ 9 Ignition/flame sense electrode ..................................................... 9 Boiler schematic ........................................................................... 10 Technical data .............................................................................. 11 Schematic wiring diagram .......................................................... 12 Fault finding ............................................................................ 13 - 16 Spare parts .................................................................................... 16

pulling down and forward out of ‘keyhole’ slots. G Unscrew and remove two screws securing heat exchanger inspection plate to flue hood. G Remove inspection plate by pulling forward and off flue hood. G Examine heat exchanger for any blockages or build up of deposits. G Clean heat exchanger with soft brush or vacuum cleaner. Reassembly of parts removed for servicing All parts are replaced in reverse order to removal. Note: 1) When refitting fan, ensure that it is pushed upwards as far as the locating lugs will allow. 2) When refitting the ignition and flame detection leads, the RED lead goes to the REAR electrode and the WHITE lead goes to the FRONT electrode. ROUTINE CLEANING AND INSPECTION To ensure the continued efficient and safe opera- tion of the boiler it is recommended that it is checked and serviced at regular intervals. The frequency of servicing will depend upon the particular installa- tion conditions and usage, but in general once a year should be enough. It is the law that any servicing is carried out by a competent person. Service Check and Preparation. G Operate boiler and check for any faults that need to be put right. G Isolate boiler from the gas and electrical supplies. G On completion check all gas carrying parts for soundness with leak detection fluid. G The maximum domestic hot water flow rate is 12 litres/minute. G Remove boiler casing as follows: Upper front panel G Remove by pulling free from the spring clips at the top and bottom. Side panels G Remove the four screws securing each panel to the boiler, two at the top, two at the bottom. G Lift off panel. Combustion chamber G Unclip four toggle clips holding the sealed chamber cover. G Unscrew and remove two screws securing sealed chamber cover to sealed chamber see diag. 1. G Remove four screws securing combustion chamber cover to combustion chamber, see diagram 2. Important: Note position of baffle secured by upper two combustion chamber cover screws. G Pull combustion chamber cover down and out of boiler, taking care not to damage insulating material on internal faces of combustion chamber. Burner G Undo main gas supply nut from burner. G Pull main burner forward, pull off the ignition and flame sense leads from the electrodes and remove burner from boiler. Note: The washer between main burner and main burner gas supply must be kept for use on reassembly. G Remove ignition and flame sense electrodes from burner. G Unscrew and remove four injector bar retaining screws and separate injector bar from burner. G Examine and clean injectors as necessary. Note: DO NOT use a wire or sharp instrument on the holes. Heat exchanger G Disconnect power supply leads from fan by separating at electrical connector. G Unscrew, but do not remove, two fan retaining screws at lower front edge of fan mounting plate. Diagram. 1 Diagram. 2

Flue system G Check externally to make sure that flue is not blocked G Inspect flue system to make sure that all fittings are secure. Operation of fan G Switch on electrical supply and turn on gas. G Set selector switch to ‘Winter’ position. G Light burner by operating external controls (if fitted) to call for heat. G Without sealed chamber cover in place, burner should be automatically prevented from lighting by air flow detection system. G Refit sealed chamber cover. G Check that fan operates when burner lights and stops when it goes out. Cold water inlet filter Drain down hot water circuit of boiler only, as follows: G Close isolating valve (c) on cold water inlet pipe, see diagram 3. Note: This valve is closed when lever is at right angles to direction of flow. G Open one or more hot water taps to drain boiler circuit. G Undo connecting nut from cold water inlet connection. G Clean and inspect filter, replace if necessary. G With both filter and restrictor in place, reconnect connecting pipe to inlet connection and tighten. G Fully open isolating valve on cold water inlet and check for leaks. Anode To inspect anode, it is necessary to drain upper sec- tion only of storage cylinder, preferably when cold. G Isolate electrical supply to boiler. G Close isolating valve (c) on cold water inlet pipe, see diagram 3. G Drain upper section only of storage cylinder by attaching a plastic tube to drain outlet and opening drain valve knob anticlockwise, see diagram 4. To assist draining, open one or more hot water taps. G Remove earth lead from connection on top of anode. G Remove anode and inspect for signs of corrosion. Important note: The anode must be checked at least once a year and in certain cases more frequent examination is recommended. If there is any sign of corrosion causing the diameter of the anode to reduce significantly, the anode must be replaced. Corrosion of the anode is a necessary process to prevent corrosion of the storage cylinder. Failure to replace the anode, when corroded, may result in considerable reduction of the life of the storage cylinder protective lining. Pla 194 b c a Unvented cylinder safety devices The unvented cylinder safety devices must be checked annually for correct operation. Proceed as follows: G Ensure that there are no persons in the vicinity of the boiler safety discharge pipes, outside the building. G Operate the combined temperature/pressure re- lief valve, using the manual lever, for a period of FIVE seconds, ensure that the valve releases safely and effectively. Diagram 3 Diagram. 4 Reg 039

be necessary to remove boiler casing panels as des- cribed in ‘Routine Cleaning and Inspection’. WARNING: Before commencing the replacement of any component, isolate appliance from electrical supply and turn off gas at service cock. To replace domestic hot water thermostat G Locate domestic hot water thermostat phial poc- ket in underside of storage cylinder. G Remove wire clip securing thermostat phial into pocket. G Remove two screws from front control panel and open panel. G Remove two leads from domestic hot water ther- mostat. G Remove domestic hot water thermostat knob by pulling off. G Using a suitable tool, unscrew and remove nut se- curing thermostat to control panel. G Fit replacement control in reverse order to remo- val. G Connect leads to terminals 1 and C. The polarity is not important. To replace fan G Remove fan as described in ‘Routine Cleaning and Inspection’. G Fit replacement fan in reverse order to removal. G Reconnect electrical lead. To replace air pressure switch G Locate air pressure switch situated outside sealed chamber on upper right hand side, see diagram 5. G Remove sealed chamber cover as described in ‘Routine Cleaning and Inspection’. G Hold air pressure switch and remove two securing screws. G Carefully pull off air sensing tubes. G Disconnect electrical leads to switch. G Fit leads to terminals of replacement switch. G Reconnect short air sensing tube to connection marked H. G Reconnect long air sensing tube to connection marked L. G Fit replacement switch to boiler in reverse order to removal. To replace printed circuit board (PCB) G Remove two screws from front control panel and open panel. G Carefully pull off electrical connections to PCB. G Unscrew and disconnect two incoming mains wi- res. G Unscrew and disconnect two mains warning light wires. G Remove screws securing PCB to control panel and lift out PCB. G Fit replacement PCB in reverse order to removal. Note: Make sure that PCB connections are fully pushed onto replacement PCB. To replace central heating thermistor Drain down heating circuit of boiler only as follows: REPLACEMENT OF PARTS G Close isolating valves on flow and return pipes on boiler, see diagram 3. Note: 1) These valves are closed when levers are at right angles to direction of flow. 2) It is not necessary to drain down entire heating system to carry out this work. G Drain boiler by attaching a plastic tube to drain outlet and opening drain valve knob anticlockwise, see diagram 4. G Locate central heating flow thermistor on central heating flow pipe below automatic air vent. G Remove electrical connections from thermistor. G Unscrew and remove thermistor from flow pipe. G Fit replacement thermistor in reverse order to remo- val. G Refit electrical connections. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace central heating temperature control G Remove two screws from front panel and open panel. G Carefully pull off central heating temperature con- trol plug from PCB terminal marked A5. G Carefully pull off two leads to ‘Summer/Winter’ switch. G Remove central heating temperature adjustment knob by pushing off with suitable tool through one of the holes in rear of control panel, see diagram 6. G Using suitable tool, unscrew and remove nut secu- ring control to control panel. G Fit replacement control in reverse order to remo- val. To replace pump G Drain down the heating circuit of the boiler only, as described previously. Note: It is not necessary to drain down entire heating system to carry out this work. G Undo two pump union nuts and pull pump forwards. Diagram. 6 Diagram. 5

Diagram. 7 Diagram. 8 Reg 018 G Undo and remove screw securing electrical cover onto pump housing and remove cover. G Disconnect electrical connections from pump. G Connect electrical connections to replacement pump and refit cover. G Fit replacement pump in reverse order to removal. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace temperature gauge G Gain access to rear of control panel. G Remove clip securing temperature gauge bulb to heating flow pipe. G Remove temperature gauge from front panel by squeezing together plastic locating tabs and pushing gauge through hole in panel. G Fit replacement gauge in reverse order to removal. Note: 1) Apply heat sink compound to bulb of replacement gauge prior to fitting. 2) Carefully route capillary to ensure it doesn’t become crushed or damaged. To replace pressure gauge G Drain down heating circuit of boiler only as described previously. G Gain access to rear of control panel. G Unscrew and remove nut securing pressure gauge capillary to hot water pipe, see diagram 7. G Remove pressure gauge from front panel by squeezing together plastic locating tabs and pushing gauge through hole in panel. G Fit replacement gauge in reverse order to removal. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. Note: Carefully route capillary to ensure it doesn’t become crushed or damaged. To replace 3-way valve head G Locate three way valve on left hand side of boiler, below sealed chamber. G Depress valve head locating button, and turn valve head 1/8th turn anti-clockwise to release from valve body. G Pull out electrical plug. G Fit replacement valve head in reverse order to removal. Note: It is not necessary to drain boiler to carry out this work. To replace 3-way valve G Drain down heating circuit of boiler only as described previously. Note: It is not necessary to drain down entire heating system to carry out this work. G Remove 3-way valve head as described previously. G Unscrew three nuts securing 3 - way valve to pipework and lift out 3 -way valve, making note of the position of valve port ‘A’. G Fit replacement valve in reverse order to removal, fitting valve port ‘A’ in the correct position. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace loss of water switch G Drain down heating circuit of boiler only as described previously. Note: It is not necessary to drain down entire heating system to carry out this work. G Locate loss of water switch on heating flow pipe to right of pump. G Disconnect electrical connections from switch. G Undo switch from pipe using suitable spanner. G Fit replacement switch into pipe, do not overtighten. G Refit electrical connections G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace gas valve module G Locate gas valve module attached to side of gas valve. G Remove screw securing cover onto gas valve mo- dule, see diagram 8. G Remove cover and disconnect multi-plug from mo- dule. G Disconnect ignition and flame sense leads from module. G Withdraw module from gas valve. G Fit replacement module, ensuring it is of the correct type for the boiler, in re- verse order to removal. G Reconnect ignition and flame sense leads, the con- nections are uniquely sized to ensure correct repla- cement. G Reconnect multi-plug onto replacement module. G Refit cover ensuring all sealing grommets are correctly located in module body. To replace gas valve G Ensure that gas supply to boiler is turned off at gas cock. G Remove gas valve module as described previously. G Disconnect electrical connections to gas valve modulating coil, see diagram 8. G Undo main gas supply nut from main burner. Note: The washer must be kept for use on reassembly. G Undo main gas union nut between gas valve supply pipe and gas inlet valve at right hand rear of boiler. Note: The washer must be kept for use on reassembly. G Unscrew and remove two screws securing gas valve fixing bracket to boiler frame.

G Withdraw gas valve assembly. G Using old gas valve as a guide, transfer gas pipes from old gas valve to replacement gas valve. G Fit replacement gas valve into boiler. G Reconnect gas pipes in reverse order to removal. G Refit electrical connections in reverse order to removal, the polarity of the wires to the modulating coil is not important. To replace modulating coil G Ensure that gas supply to boiler is turned off at gas cock. G Disconnect electrical connections to gas valve modulating coil, see diagram 8. G Undo two screws securing modulating coil to gas valve and remove coil. G Fit replacement coil in reverse order to removal. G Refit electrical connections in reverse order to removal, the polarity of the wires to the modulating coil is not important. To replace central heating safety valve If safety valve seating is damaged, it will be necessary to replace safety valve as a complete unit, repair is not possible. G Drain down heating circuit of boiler only as described previously. Note: It is not necessary to drain down entire heating system to carry out this work. G Disconnect safety valve discharge pipe from safety valve. G Remove safety valve from boiler pipework, see diagram 7. G Fit replacement safety valve in reverse order to removal. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace temperature/pressure relief valve (T&P valve) To replace T&P valve, it is necessary to drain upper section only of storage cylinder, preferably when cold. G Isolate electrical supply to boiler. G Close isolating valve (c) on cold water inlet pipe, see diagram 3. G Drain upper section only of storage cylinder by attaching a plastic tube to drain outlet and opening drain valve knob anticlockwise, see diagram 4. To assist draining, open one or more hot water taps. G Locate T&P valve on upper part of storage cylinder. G Disconnect T&P valve discharge pipe. G Unscrew and remove T&P relief valve. G Fit replacement T&P valve in reverse order to removal using a Water Research Centre approved sealant suitable for potable water. G Open isolating valve (c) on cold water inlet connection on fixing jig, see diagram 3. G Refill storage tank and vent cylinder. G Check for leaks. To replace anode To replace anode, it is necessary to drain upper sec- tion only of storage cylinder, preferably when cold. G Isolate electrical supply to boiler. G Close isolating valve (c) on cold water inlet pipe, see diagram 3. G Drain upper section only of storage cylinder by attaching a plastic tube to drain outlet and opening drain valve knob anticlockwise, see diagram 4. To assist draining, open one or more hot water taps. G Remove earth lead from connection at top of anode. G Unscrew and remove anode from storage cylinder. G Fit replacement anode in reverse order to removal. G Open isolating valve (c) on cold water inlet pipe, see diagram 3. G Refill storage tank and vent cylinder. G Check for leaks. To replace heat exchanger G Drain down heating circuit of boiler only as described previously. Note: It is not necessary to drain down entire heating system to carry out this work. G Remove fan as described in ‘Routine Cleaning and Inspection’. G Undo two nuts securing heating flow and return pipes to sealed chamber bulkhead fittings, see diagram 9. G Undo nuts on heating flow and return connec- tions on heat exchanger. G Undo nuts securing sealed chamber bulkhead fittings to sealed chamber and remove pipes and fittings from boiler. Note: Keep washers for use on reassembly. G Remove spring clip securing flue hood to heat exchanger pipe and withdraw flue hood forwards and out of boiler. G Disconnect electrical connectors from high limit thermostat. G Lift heat exchanger up and out of combustion chamber and remove from boiler. G Fit replacement heat exchanger in reverse order to removal. G Reconnect electrical connections to high limit thermostat, the polarity is not important. G Reconnect heating connections using new washers supplied. G Replace flue hood and fan in reverse order to removal. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace expansion valve G Close isolating valve (c) on cold water inlet pipe, see diagram 3. G Locate expansion valve at base of G Disconnect pipework to expansion valve and remove valve from boiler. G Fit replacement expansion valve in reverse order to removal. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks.

combustion chamber cover. Rear panel: G Lift rear insulation panel free from retaining lug at rear of combustion chamber by tilting forward. Side panels: G Lift side panels free from retaining lugs on combus- tion chamber sides by tilting slightly. G Fit replacement insulation panels in reverse order to removal G Refit combustion chamber cover, heat exchanger, flue hood and fan in reverse order to removal. To replace burner G Remove burner as described in 'Routine Cleaning and Inspection'. Assemble replacement burner, supplied in parts, as follows: G Fit burner injectors to burner injector bar and tighten. Note: Make sure that injector size, marked on each injector, is the same as that given in ‘Technical Data’ for the type of gas being used. G Fit injector bar into burner, secure using four screws. G Fit replacement burner into boiler in reverse order to removal. To replace burner injectors G Remove burner as described in 'Routine Cleaning and Inspection'. G Unscrew and remove four injector bar retaining screws and separate injector bar from burner. G Unscrew and remove injectors from injector bar. G Fit replacement injectors to injector bar and tighten. Note: Make sure that injector size, marked on each injector, is the same as that given in ‘Technical Data’ for the type of gas being used. G Reassemble burner and fit into boiler in reverse order to removal. To replace ignition/flame sense electrode G Remove burner as described in ‘Routine Cleaning and Inspection’. G Undo and remove screw securing electrode onto burner. G Fit replacement electrode onto burner in reverse order to removal. G Refit burner into boiler in reverse order to removal. REPLACEMENT OF PARTS To replace central heating expansion vessel G Drain down heating circuit of boiler only as described in 'To replace pump'. Note: It is not necessary to drain down entire heating system to carry out this work. G Isolate electrical supply to boiler. G Undo pipe coupling at base of expansion vessel. G Supporting expansion vessel, unscrew and remove screws securing expansion vessel to boiler. G Lift vessel out of boiler. G Fit replacement vessel to boiler in reverse order to removal, ensuring that sealing washer is fitted to pipe connection before tightening. G Ensure that expansion vessel charge pressure is 1,0 bar (15 psi) using a pressure gauge. If necessary, increase pressure using a car or cycle tyre pump connected to the Schrader valve. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace domestic expansion vessel To replace domestic expansion vessel it is necessary to drain entire storage cylinder, preferably when cold. G Isolate electrical supply to boiler. G Close isolating valve (c) on cold water inlet pipe, see diagram 3. G Drain upper section only of storage cylinder by attaching a plastic tube to drain outlet and opening drain valve knob anticlockwise, see diagram 4. To assist draining, open one or more hot water taps. G Undo pipe coupling to expansion vessel. G Undo nut securing expansion vessel to boiler. G Lift expansion vessel out of boiler. G Fit replacement vessel to boiler in reverse order to removal, ensuring that sealing washer is fitted to pipe connection before tightening. G Ensure that expansion vessel charge pressure is 3 bar (45 psi) using a pressure gauge. If necessary, increase pressure using a car or cycle tyre pump connected to the Schrader valve. G Open isolating valves on flow and return connec- tions, refill, vent and pressurise boiler. G Check for leaks. To replace high limit thermostat G Locate high limit thermostat on left hand side of heat exchanger below central heating flow connection, see diagram 9. G Disconnect two electrical connectors from thermos- tat G Unscrew and remove two self tapping screws securing thermostat to heating flow pipe. G Remove thermostat. G Fit replacement thermostat in reverse order to removal using heat sink compound supplied. G Reconnect two leads to thermostat, the polarity is not important. To replace combustion chamber insulation G Remove fan, flue hood and heat exchanger as described in ‘To replace heat exchanger’. G Unscrew and remove four screws securing combus- tion chamber cover to combustion chamber. G Remove combustion chamber cover. Diagram. 9

17 - Expansion valve (6 bar) 18 - Domestic expansion vessel 19 - Drain valve 20 - Fan 21 - Air pressure switch 22 - Temperature/pressure relief valve (7 bar) 23 - Tundish 24 - Non-return valve A - Heating return B - Cold water inlet C - Heating flow D - Domestic hot water flow F - Gas supply 1 - 3-way valve 2 - Loss of water switch 3 - Pump 4 - CVI unit 5 - Gas valve 6 - Ignition electrode 7 - Injector manifold 8 - Flame detection electrode 9 - Heat exchanger 10 - Bleed valve 11 - Thermistor 12 - Expansion vessel 13 - Anode 14 - Cylinder 15 - Domestic thermostat 16 - Overheat safety thermostat Shy 115UK H L 21 10 11 19 20 21 13 14 15 6 7 8 9 A B C D F 1 2 12 3 4 5 17 18 16 23 22 24

36,850 BTU/H to 81,890 BTU/H Efficiency 81 % Maximum heating temperature 90 °C Expansion vessel effective capacity 7,5 l Expansion vessel charge pressure 1,0 bar Maximum system capacity at 75°C 170 l Safety valve, maximum service pressure 3 bar Products outlet Ø 60 mm Fresh air inlet Ø 100 mm Hot water output automatically variable from 10,8 kW to 24 kW 36,850 BTU/H to 81,890 BTU/H Storage capacity 60 l Maximum hot water temperature 65 °C Specific flow rate (for 30°C temperature rise) 13,6 l/min. Nominal water flow rate 10 l/min. Expansion vessel effective capacity 2 l Expansion vessel charge pressure 3 bar Maximum supply pressure 10 bar Maximum operating pressure 3,5 bar Temp./press. relief valve opening pressure 7 bar Temp./press. relief valve opening temperature 90 °C Cylinder heat up time 7 min. Time to reheat 70% of storage to 65°C 3 min. Expansion valve setting 6 bar Weight when full 144 kg Electrical supply 230 V Maximum absorbed power 165 W Level of protection IP44 Natural Gas Butane Propane (G20) (G30) (G31) Burner injector 1,20 mm 0,77 mm 0,77 mm Inlet pressure 20 mbar 28 mbar 37 mbar Gas rate (maximum) 2.81 m3/h 2,10 kg/h 2,06 kg/h Gas rate (minimum) 1,32 m3/h 0,98 kg/h 0,97 kg/h Gas (reference 15° - 1013 mbar) Burner pressures : burner pressures, as listed in the table below, must be checked after the boiler has been operating for 3 minutes. Table 1 0 10 20 500 1000 1500 30 40 50 Pression disponible (kPa) entre départ et retour chaffage Débit dans le circuit chaufage (l/h) (10 kPa = 1 mCE) 0 30 35 30 60 90 120 150 180 210 240 40 45 50 55 60 65 Température de soutirage en °C Quantité d'eau soutirée en litres Water draw off temperature in °C Flow rate through heating system (l/h) Available pressure between heating flow and return (kPa) 10 kPa = 1 mWG Water draw off in litres Pump : Domestic hot water production : Temperature of cold water = 15°C Temperature of stored water = 60°C Drawing off at 12 l/min. Diagram. 11 Heat output (kW) 10,8 11 12 13 14 15 16 17 18 19 20 21 22 23 24 (Btu/h) 36850 37532 40944 44356 47768 51180 54592 58004 61416 64828 68240 71652 75064 78476 81888 Heat input (kW) 13,9 14,1 15,3 16,6 17,8 19,0 20,2 21,4 22,6 23,8 24,9 26,1 27,3 28,4 29,6 (Btu/h) 47389 48115 52326 56510 60668 64800 68907 72989 77045 81077 85084 89067 93026 96961 100872 GAS G 20 (mbar) 3,1 3,4 3,5 4,1 4,7 5,4 6,1 6,8 7,6 8,4 9,2 10,1 11,1 12,0 13 G 30 (mbar) 5,8 6,3 6,9 8,1 9,3 10,6 12,0 13,5 15,0 16,6 18,3 20,0 21,9 23,7 25,7 G 31 (mbar) 7,6 8,0 9,1 10,6 12,3 14,0 15,8 17,7 19,8 21,9 24,1 26,4 28,8 31,3 33,9

Diagram. 12 1110 9 8 7 6 5 5 4 3 2 1 6 5 4 3 2 1 9 8 7 6 5 4 3 2 1 4 3 2 1 CTN EV1 K5 E/H TH TA V2 P IG 230V N L L.alim. P1 L2 L1 L3 P3 A5 6 5 4 3 2 1 A2 A4 A7 A3 A1 F1 - 4A Rel3 Rel2 Rel4 SW2 TRA Rel1 F2 - 125mA F3 315mA Pr EX NO C NC + - EV FA FL BR LK4 K4 ACF ACF .................................... Flame control circuit A1 ...................................... 230V Connector A3-A5 ................................ 24V Connectors A7 ...................................... Clock option connector BR ....................................... Reset button CTN .................................... Thermistor EV1 ..................................... Modulating valve EV ....................................... Main gas valve EX ....................................... Fan E/H ..................................... ‘Summer/Winter’ switch F1, F2, F3 ............................ Fuses FA ....................................... Ignition elctrode FL ........................................ Flame sense electrode IG ....................................... Mains ON/OFF switch K4 ....................................... Overheat thermostat K5 ....................................... Loss of water switch LK4 ..................................... Safety reset light L.alim ................................. Mains supply light L1,L2,L3 .............................. Diagnostic LED's P ......................................... Pump Pr ........................................ Air pressure switch P1 ....................................... Heating temperature control P3 ....................................... Heating range rating adjuster Rel1,Rel2,Rel3,Rel4 ........... Relays SW2 .................................... Fan option shunt TA ....................................... Room thermostat TH ....................................... Cylinder thermostat V2....................................... Three way valve

G All gas supply cocks are open and that the gas supply has been purged of air. G The heating system pressure is at least 1 bar. G There is a permanent mains supply to the boiler. G The fuses on the PCB are intact. G The ‘Summer/Winter’ switch is in the heating or heating and hot water position. The fault finding charts will enable the majority of faults to be diagnosed. To use the charts effectively, it is necessary to determine exactly which aspects of the boiler are working correctly and which are not. For example: If the domestic hot water works but the heating doesn’t, refer to chart No. 1. If heating works correctly but the hot water doesn’t, refer to chart No. 2. IMPORTANT: Always adopt a logical, step by step procedure starting at the beginning of the appropriate fault finding chart. WARNING. Always isolate the boiler from the electrical supply before carrying out any electrical replacement work. Always check for gas soundness after any service work. T (°C) 0 3 6 9 0....................33242 ..................28409 .............. 24361............. 20958 10...................19947 ..................17233 .............. 14934............. 12979 20...................12394 ..................10813 ............... 9459............... 8297 30....................7947....................6995................6171...............5458 40....................5242....................4651................ 4136............... 3685 50....................3548....................3171................ 2840............... 2548 60....................2459....................2212................ 1994............... 1800 70....................1740....................1580................ 1428............... 1297 80....................1256 ................... 1143................ 1042................ 952 90.....................932 ......................845.................. 774................. 710 100....................690 ......................634.................. 584................. 538 Thermistor values Example : At 36°C, the thermistor resistance will be 6171 Ω At 80°C, the thermistor resistance will be 1256 Ω

NO CENTRAL HEATING CHART N° 2 NO DOMESTIC HOT WATER NO NO NO NO NO NO NO NO NO NO YES YES YES YES YES YES YES Does burner fire? Refer to chart No.3. Set controls to call for heat. Are external controls wired? Rectify wiring. Is burner pressure correct? - Refer to technical data. Heating ok. Is the range rating potentiometer correctly adjusted? Adjust potentiometer to required setting - does potentiometer adjust burner pressure? Faulty potentiometer - replace PCB. YES YES Does burner fire when a hot tap is opened for approximately 3 minutes ? Is plug to the external controls connected to the boiler ? Connect external controls plug. Remove leads from central heating thermistor. Check its resistance in accordance with diagram 17 - is central heating thermistor OK ? Remove potentiometer connec- tor from A5 on PCB. Check resis- tance of heating potentiometer between white and black leads - does it adjust between 0-1 kΩ ? Replace central heat- ing potentiometer Replace central heating thermistor Faulty PCB - replace Are heating controls calling for heat ? NO NO NO NO NO YES DHW ok. Replace domestic hot water thermostat Replace 3 - way valve head Refer to chart N°5 NO NO NO YES YES YES YES YES YES With the "Summer/winter" switch in the winter, hot water and central heating position - does the burne fire for central heating ? Refer to chart No.3. Remove domestic hot water thermostat connector from A3 on PCB. Turn thermos- tat up maximum - Is there continuity bet- ween the two thermostat leads ? Check PCB - replace if necessary Replace domestic hot water thermostat Is the hot water hot enough ? Adjust domestic hot water thermostat Is the domestic hot water thermostat set to the desired position ? Check operation of 3 - way valve - is there flow of hot water to storage cylinder flow pipe ? Is domestic hot water thermostat working correctly, that is, by turning to maximum does burner fire, by turning to minimum does burner go out ? Operate 3 - way valve manually - is there flow of hot water to storage cylinder flow pipe ? Does the burner fire when a hot tap is opened for aproximately 3 minutes ?

BURNER WILL NOT FIRE (AFTER REFER- RING TO CHART 1 OR 2) NO YES YES YES NO NO Does fan run ? Fan OK Faulty PCB-replace Faulty fan-replace Chek PCB - is there 230 V ac between PCB connections A.2.1 and A2.2 ? Check fan wiring loom - is there 230 V ac at fan motor ? Faulty fan wiring loom - rectify/replace as necessary CHART N° 4 FAN NOT RUNNING NO YES YES YES YES YES YES NO NO YES NO NO NO NO NO Does burner fire on central heating or hot water ? is the flue corrctly fitted and free of obstructions ? Check for correct fit of sealed chamber cover Is pump running at full speed ? Does burner remain on for less than 5 seconds ? Is fan running at full speed ? Refer to chart N°4 Refer to chart N°5 Is there circulation in the heating circuit? Check : - Boiler isolating valves are open. - Radiator valves are open (or system bypass is fitted) - No air is trapped in system Rectify flue Check air pressure switch - is there 230 V ac between PCB connections A2.4 and A1.2 Check for 230 V ac at gas valve -is there 230 V ac between PCB connections A1.1 and A1.2 ? Does burner light and then go out ? Replace air pressure switch Replace gas valve Faulty PCB - replace Boiler ok. YES

the appliance model number and serial number from the data badge. Short parts list No. Description Part No. 1 Domestic hot water thermostat 56013 2 Fan 56118 3 Air pressure switch 56008 4 Printed circuit board 56254 5 Central heating thermistor 56014 6 Pump 56128 7 Temperature gauge 56010 8 Pressure gauge 56005 9 3-way valve head 51335 10 Gas valve module 56024 11 Central heating safety valve 56110 12 Expansion valve (6bar) 56029 13 T&P relief valve (7bar) 56108 14 Anode 56000 15 High limit thermostat 56012 16 Ignition/flame sense electrode 56002 85890 B 07/97 CHART N° 5 PUMP NOT RUNNING SPARE PARTS NO NO NO NO YES YES YES NO NO Does pump run? Remove cap on front of pump. Using screwdriver, press in and rotate the slotted shaft clockwise - do not hit shaft. Open auto air vent on pump. Check PCB - is there 230 V ac between PCB connections A1.3 and A1.4 Faulty pump wiring loom - rectify/replace as necessary. Faulty PCB - replace Faulty pump - replace Is there 230 V ac at pump motor ? Pump ok. Is pump free to rotate? Is there air in pump? YES