Ideal Boilers Classic RS 300 Installation & Servicing Manual

Ideal Boilers Classic RS 300 Installation & Servicing Manual Manual pdf 28 page image

28Classic RS - Installation & ServicingFAULT FINDINGReset the overheat 'stat. Set control'stat to maximum. Allow the boiler toreach temperature - if the overheat'stat trips again, measure flowtemperature.If above 90°C replace control 'stat.If below 90°C replace overheat 'stat.STARTCheck that the Mains Onneon 'I3' is illuminated.YESNOIs there a live supply to bothterminals of overheat 'stat?YESYESCheck mains supply and fuses.Check programmer and systemthermostats are all ON.Check mains input is sound.Check that the boilerthermostat is set at maximum.Is the ignition electrodesparking ?Check all connections to PCB.If no fault found change PCB.Does the pilot light ?YESDoes the spark stopafter pilot is lit?Is there a gas supplyto the boiler?Is the pilot injectorblocked?YESNOIs there a regular spark fromtube 'SG1' on the PCB?Can the overheat 'stat be resetwhen the system is cold ?NOYESNOReplace fuse BUT, beforeattempting to start boiler, check forshort between live and neutral,also between live and earth, on allitems plugged into the PCB.Has the fuse blown on PCB ?Replace the overheat thermostatCheck gap at ignition electrode.Check electrode and lead areundamaged, and not close toearthed metalwork.NONOYESNOYESHas the gas line beenpurged of air ?YESReplace gas valveNOEnsure pilot andmain gas valve leadsare not crossed over.Is there a supplyvoltage at pilot gasvalve?YESNOYESCheck all connections to PCB.If no fault found, replace PCB.YESNOIs there a supply on terminals ofmain gas valve?YESNOCheck the polarity ofthe mains supply.Check the continuity ofthe ignition lead fromconnector to electrode.Does the spark nowcease when gas is lit ?NODoes main burner cross-light from pilot?Is the main burnerinjector clear?Replace main gassolenoid valveNOFAULT FINDING FAULT FINDING FAULT FINDING FAULT FINDING FAULT FINDING FAULT FINDING