16 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Greenstar 30si Compact
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Your boiler is currently struggling to measure the temperature of the water it is heating, which means it will stop providing you with hot water.
Your boiler has lost its connection to the remote programmer or thermostat on your wall, preventing it from receiving instructions on when to turn the heating on.
Your boiler's internal computer is struggling to identify the specific settings it needs to operate, so it has safely shut down to prevent incorrect functioning.
Your boiler has detected that the water inside it is very cold and has automatically activated its internal frost protection system to prevent the pipes from freezing.
Your boiler has detected that the internal fan responsible for clearing exhaust gases is not spinning at the correct speed to operate safely.
Your boiler has detected that the water is flowing through your hot water system faster than it can heat up, which often points to an issue with how much water is being drawn from your taps.
Your boiler is struggling to accurately measure its own temperature, so it has safely shut itself down to prevent potential damage.
Your boiler has lost the ability to measure the temperature of the water used for your radiators, so it has safely shut down to prevent overheating.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler is trying to start up but cannot light the internal flame, so it has shut itself down as a safety precaution.
Your boiler has detected an internal computer error and has shut down for safety reasons.
Your boiler is detecting a flame inside even when it is turned off, which prevents it from starting to avoid a safety hazard.
Your boiler has detected a flame even though it has commanded the gas supply to turn off, which means it must be turned off immediately for safety.
Your boiler is perfectly safe and functional, but it has detected that the reset button was held down for too long, essentially pausing the system as a precaution.
Your boiler has failed to light the flame after several attempts and has shut itself down as a safety precaution.
Your boiler is performing a routine maintenance check to ensure your water pump stays in good working condition.
BoilerFaultCodes