23 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's internal memory chip is not communicating correctly with the main control board, preventing the system from starting up.
Your boiler’s internal computer chip has encountered a communication error or is missing, preventing the system from running safely.
Your boiler is failing to start because it has lost the ability to safely manage the ignition process.
Your boiler is failing to communicate with its built-in internal memory chip, meaning it cannot access the configuration information needed to run properly.
Your boiler is experiencing a communication fault within its internal wiring, meaning it cannot properly send or receive the signals needed to operate safely.
Your boiler has detected an issue with the ignition process, meaning it is unable to safely light the flame required to produce heat.
Your boiler has detected an issue with how the gas is being delivered to the burner, meaning it cannot safely ignite or heat your home.
Your boiler has detected an issue with the fuel supply settings and has switched itself off to stay safe.
Your boiler is struggling to bring in the correct amount of air needed to burn gas safely.
Your boiler is struggling to get the right balance of air and gas to burn safely, which is often caused by the wrong internal setting or part being installed for the type of gas you are using.
Your boiler's main control computer is missing a vital activation chip, which means the system cannot start up or provide any heat.
Your boiler has detected that the water pressure in the system is too low, causing it to stop running for safety.
Your boiler has lost its flame signal during operation, meaning and it can no longer safely heat your water or radiators.
Your boiler has detected an issue with its fan, meaning it cannot safely circulate air or clear exhaust fumes and has shut down as a safety precaution.
Your boiler has detected that a temperature sensor is not communicating correctly, meaning the system cannot tell how hot the water is and has stopped working for safety.
Your boiler has stopped working because it cannot properly measure the temperature of the water coming back from your radiators.
Your boiler has lost communication with the sensor that measures the temperature outside, which helps it run more efficiently.
Your boiler has detected that the electricity supply coming into your home is at a lower voltage than it needs to operate safely.
Your boiler's internal computer has encountered a critical error and cannot communicate with the rest of the system.
Your boiler has shut down because the water inside it has become too hot, likely due to a circulation problem.
Your boiler has lit correctly but the flame has gone out unexpectedly, often due to a fuel supply issue or a blockage in the condensate pipe.
Your boiler has been manually reset too many times in a short period and has locked itself out to prevent further damage or safety issues.
Your boiler thinks it sees a flame even though it isn't currently trying to light, causing the system to shut down for safety.
BoilerFaultCodes