11 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Greenstar 30 Si
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Your boiler's temperature sensor for hot water has stopped working properly, meaning your taps may only provide cold or lukewarm water.
Your boiler has temporarily lost communication with its electronic room thermostat or control unit.
Your boiler's computer memory chip is loose or missing, meaning the system doesn't know which model it is and has stopped working for safety.
Your boiler’s internal fan is not spinning fast enough to safely clear away exhaust fumes, which has caused the system to shut down for safety.
Your boiler has detected a faulty internal temperature sensor, which means it cannot accurately monitor the water temperature and has shut down as a safety precaution.
Your boiler has shut down because it has detected that the water inside is Getting too hot, which is a safety feature to prevent damage.
Your boiler is failing to light the gas or isn't detecting that the flame has started, causing the system to shut down for safety.
Your boiler thinks it can see a flame inside the system even though it should be turned off, which is a safety conflict that prevents it from starting up.
Your boiler is still detecting a flame even though it has tried to shut off the gas, which is a safety conflict causing the system to lock out.
Your boiler has been put into a temporary reset mode because the button was held down too long or pressed accidentally.
Your boiler has detected an internal computer error and has safely shut down to prevent any further issues.
BoilerFaultCodes