Error codePossible faultInstaller action
LIGHTS ARE:Fan FaultIsolate The Electrical Supply To The Boiler (The Fan Is 325Vdc); Check Wiring From PCB To Fan.
FLASH FLASH ONReplace The Fan, If Problem Persists, Change PCB;
LIGHTS ARE:Incoming Voltage Less Than 180VCheck supply to appliance.
FLASH OFF FLASH
LIGHTS ARE: FLASH OFF ONOverheat LockoutCheck The Black Overheat Stat On The Flow Pipe Has Continuity When Disconnected;Check Black Overheat Stat On The Fan Has Continuity When Disconnected; Check The Combustion Box Door Seals And Burner Condition (Leaking Door Can Trip The Fan Stat And Also Damage The Burner).
LIGHTS ARE:PCB Fault
FLASH ON FLASH
LIGHTS ARE: FLASH ON ONPCB Fault
LIGHTS ARE: OFF OFF OFFNo Power SupplyCheck power into appliance should be 230v ac, if OK suspect PCB.
LIGHTS ARE: ON FLASH FLASHNo Circulation/Dry FireCheck The System Is Full Of Water; Check For Blockage In System; If There Is Continuity Across The Primary Flow Switch When It Is Unplugged And The Pump Is Running, Replace The PCB. If There Is No Continuity When The Pump Is Running check pipework to the boiler is correct then Replace The Flow Switch.
LIGHTS ARE: ON FLASH ONThermistor FaultCheck Wiring From PCB To Flow Thermistor; If Wiring Ok Unplug Flow Thermistor And Check Resistance Is Between 0.5K And 20K; If Flow Thermistor OK Then Replace PCB.
LIGHTS ARE: ON OFF FLASHLive And Neutral ReversedLive And Neutral Reversed Into The Boiler.
LIGHTS ARE: ON OFF ONIgnition LockoutCheck Gas Supply, Pre-Paid Meters Etc. Gas {pressure Should Be Greater Than 18Mb.
Check Condensate Trap Is Not Blocked And Trip Connections Are Dry;
Check Spark Gap Is Between 3-5MM;
Check Wiring From PCB To Electrode Is OK;
Check There Is 215-240V To The Gas Valve During Ignition Phase;
Check for flue blockage.
LIGHTS ARE: ON ON FLASHPCB Fault
LIGHTS ARE: ON ON ONLow Voltage Wiring Harness Fault

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