6 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic System
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Your boiler’s internal computer has encountered a critical communication error and can no longer control the heating or hot water functions.
Your boiler has detected that the gases being sent out through your flue are reaching dangerously high temperatures and has shut itself down to prevent damage or fire risk.
Your boiler has shut down because the internal gases have become too hot, causing the system to lock out for safety until it cools down.
Your boiler's computer system is experiencing a major internal processing error and cannot safely manage the heating process.
Your boiler is failing to light the internal flame or keep it burning, which means your heating and hot water have stopped working.
Your boiler has detected that the gases leaving through the flue are getting too hot, so it has automatically shut itself down to prevent damage.
BoilerFaultCodes