BoilerFaultCodes.com

Ferroli Ferroli Boiler Error Codes Fault Codes

Oil Natural Gas

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Most common fault codes

A01
Your boiler has failed to light the flame, which means you will not have any heating or hot water until the issue is resolved.
May be DIY safe · £90-280
A02
Your boiler is failing to detect a flame because of a communication fault between the internal electronics and the ignition component.
Gas Safe engineer required · £120-350
A03
Your boiler has likely overheated because water isn't moving through the pipes correctly or there is too much trapped air in the system.
May be DIY safe · £100-280

All 20 fault codes

Code Severity Plain English
A01 High Your boiler has failed to light the flame, which means you will not have any heating or hot water until the issue is resolved.
A02 High Your boiler is failing to detect a flame because of a communication fault between the internal electronics and the ignition component.
A03 High Your boiler has likely overheated because water isn't moving through the pipes correctly or there is too much trapped air in the system.
A06 High Your boiler is struggling to keep a flame lit because it isn't receiving enough gas or the pressure is too low to stay running.
A09 High Your boiler has stopped working because it cannot communicate properly with the gas valve that controls the fuel supply.
A15 High Your boiler has developed a recurring problem with how it clears exhaust fumes and has locked itself out for safety after multiple failures.
A16 High Your boiler has detected a problem with its gas supply system or internal control valve, meaning it cannot safely ignite to provide heating or hot water.
A23 High Your boiler's internal computer has become confused by its own settings and can no longer communicate correctly with the system.
A24 High Your boiler’s internal computer has become confused by its own settings and doesn't know how to operate correctly.
F04 High Your boiler’s internal computer has been set up with the wrong configuration details and cannot operate safely.
F05 High Your boiler has detected a problem with how it disposes of waste gases, often caused by a blockage or a fault in the air flow system.
F07 High Your boiler has detected that a safety sensor is stuck in the wrong position, preventing the fan from starting up correctly to clear waste gases.
F10 High Your boiler's internal thermometer that measures water temperature is faulty or has a wiring issue, preventing the system from heating up safely.
F11 Medium Your boiler is struggling to provide hot water because its internal temperature sensor has stopped sending a reliable signal.
F34 High Your boiler is not receiving enough electricity from the power grid to operate properly, causing it to shut down for safety.
F35 Medium Your boiler is struggling because the electricity supply from the national grid or your home's wiring is unstable or at the wrong frequency.
F37 High Your boiler has detected that the water pressure in the system is too low for it to operate safely.
F43 High Your boiler has stopped to prevent overheating because it cannot move water through the system properly or there is an air pocket trapped inside.
F50 High Your boiler’s main control board has detected an internal computer failure, which means the system cannot manage itself safely and has stopped working.
F51 High Your boiler's main internal computer has likely developed an electrical fault and can no longer control the system safely.

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