23 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working because one of its internal sensors is sending an incorrect signals or has disconnected, preventing it from heating your water safely.
Your boiler has switched itself off because the water inside the system has become too hot.
Your boiler has shut down because the hot water has reached a temperature that is dangerously high.
Your boiler has shut down because the internal gases leaving the system have become too hot, which is a safety feature to prevent damage to the internal components.
Your boiler is trying to start up but cannot successfully light the gas to create a flame.
Your boiler is struggling to keep a flame lit after it has already started, which prevents it from heating your home properly.
Your boiler thinks it sees a flame even when it hasn't actually started the ignition process, causing it to shut down for safety.
Your boiler is failing to detect a flame, which prevents it from heating up even if it seems to be trying to start.
Your boiler has shut down because the internal fan is not spinning at the correct speed to safely clear exhaust fumes.
Your boiler's main internal computer has developed a technical hardware fault and is unable to operate the heating or hot water.
Your boiler has detected a problem with its internal temperature sensors, meaning it cannot accurately measure how hot the water is and has stopped running for safety.
Your boiler has detected a problem with its internal temperature sensors, meaning it cannot accurately measure how hot the water is and has stopped running for safety.
Your boiler has detected a problem with its internal temperature sensor, which means it cannot accurately monitor the water heat and has stopped working for safety.
Your boiler has detected that a temperature sensor is not attached correctly or is loose, preventing it from heating your home safely.
Your boiler has stopped working because one of its internal heat sensors has come loose or is not sitting correctly against the pipework.
Your boiler has detected an internal communication error or a connection issue with a sensor that monitors the main heat exchanger.
Your boiler has shut down because it cannot breathe properly, likely due to a blockage in the pipes leading to the outside of your home.
Your boiler has encountered an internal communication error between its main control boards, causing it to shut down for safety.
Your boiler has lost its connection to the outside temperature sensor, which usually helps the system adjust its heat based on the weather.
Your boiler has failed to restart correctly after multiple manual reset attempts in a short period of time.
Your boiler is unable to safely control the flow of gas required for ignition and operation, causing the system to shut down.
Your boiler has stopped working because one of its internal heat sensors is reporting a fault, meaning the system can no longer safely monitor the water temperature.
Your boiler has stopped working because it cannot detect any water flowing through the system, meaning it cannot safely heat your home or water.
BoilerFaultCodes