10 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
The fault code is already on your display
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Your boiler has lost the ability to accurately measure the temperature of your hot water, so it has shut down to prevent overheating.
Your boiler has lost the ability for its internal parts to 'talk' to each other, meaning it has safely shut down until the connection is restored.
Your boiler's electronic control system is failing to communicate with a key internal part, which is currently preventing the unit from operating safely.
Your boiler is struggling to breathe properly because its internal ventilation fan is not spinning fast enough to clear fumes safely.
Your boiler has detected that the internal fan is spinning faster than it should, so it has safely shut itself down to prevent any issues.
Your boiler has detected that water is flowing through your heating system faster than the pump can safely manage.
Your boiler's internal thermometer is not sending a proper signal, so the system has shut down its heating and hot water functions to avoid overheating.
Your boiler is trying to start but the flame is failing to ignite or stay lit, so it has shut down as a safety precaution.
Your boiler has detected that a flame is still burning inside even though it has commanded the gas supply to turn off, which is a significant safety precaution.
Your boiler is simply indicating that the reset button was pressed when there wasn't an actual fault, so it just needs a moment to restart normally.
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BoilerFaultCodes