4 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Greenstar Highflow 440 CDi
The fault code is already on your display
Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
Tap any card for details
Your boiler has detected that the water storage tank has become too hot and has automatically shut down to stay safe.
Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage or fire risk.
Your boiler has switched itself off because it detected that the water inside it has become too hot, likely as a safety precaution.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
BoilerFaultCodes