8 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: CDi Classic
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Your boiler has detected that the internal fan is moving too slowly to safely vent waste gases, so it has stopped working as a precaution.
Your boiler has detected that the internal fan is spinning faster than it should be, so it has automatically stopped working to stay safe.
Your boiler has detected that the fan, which is essential for safely venting exhaust gases, is not spinning at the correct speed.
Your boiler has lost the ability to read the temperature of the water used for your radiators, causing it to shut down for safety.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage or dangerous pressure levels.
Your boiler is failing to light the internal flame needed to heat your home's water.
Your boiler’s internal safety sensor thinks a flame is present even though it is supposed to be switched off, which has caused the system to shut down to prevent a dangerous situation.
Your boiler has detected that a flame is still burning even though it has tried to turn the gas supply off, which indicates a serious safety sensor issue.
BoilerFaultCodes