19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is currently running a routine self-cleaning process to remove trapped air from the system.
Your boiler has lost its specific 'tuning' settings which control how much power it should use, preventing it from starting up correctly.
Your boiler has detected a temperature difference between its internal pipes while it is turned off, causing it to temporarily pause for safety.
Your boiler has switched itself off because the waste gases exiting the flue are dangerously hot, indicating your system is struggling to vent heat properly.
Your boiler has stopped working because a sensor that monitors the exhaust gases has become disconnected.
Your boiler has detected a faulty sensor that monitors exhaust fumes, so it has purposefully shut down for safety reasons until the part can be replaced by a qualified engineer.
Your boiler is struggling to detect water moving through its system and is currently running a self-clearing cycle to flush out trapped air.
Your boiler has detected that the electricity supply coming from your wall socket is unstable or outside of the standard frequency range, preventing it from operating safely.
Your boiler is displaying a list showing the history of recent technical faults rather than a single active problem, suggesting the system has recorded errors while trying to manage its own performance.
Your boiler is struggling to light its internal flame properly, meaning it cannot produce heat or hot water reliably.
Your boiler has detected an electrical fault in its internal control system that is preventing it from operating safely.
Your boiler has stopped working because it cannot light the internal flame needed to heat your water and home.
Your boiler has detected an internal fault that is preventing it from operating, which usually indicates an issue with the electrical system or the main circuit board.
Your boiler's main computer brain is having a communication failure, which means the system cannot safely operate and has shut down.
Your boiler has stopped working because a small internal fuse that protects its main control system has blown, cutting off the power needed for it to operate.
Your boiler's computer has detected an internal communication failure, meaning it cannot safely operate or start up.
Your boiler is unable to confirm that its built-in fan is spinning correctly, so it has safely shut down to prevent unsafe operation.
Your boiler has stopped working because the water pressure inside the system is too low to run safely.
Your boiler has detected that the water pressure in your heating system is too high, which could cause a leak or damage if not addressed.
BoilerFaultCodes