8 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has registered an internal system hold and requires a qualified heating engineer to properly diagnose and service the unit.
Your boiler has registered an internal configuration error that requires professional attention from a heating engineer.
Your boiler has detected that the gases moving through your flue are getting dangerously hot, so it has automatically shut itself down to prevent damage.
Your boiler has registered a system instruction to consult the installation manual for a specific configuration or wiring check.
Your boiler is trying to start up, but it cannot successfully catch a flame and has locked itself out for safety.
Your boiler is trying to start up three times but is failing to ignite, meaning you currently have no heating or hot water.
Your boiler has stopped working because it tried to ignite but failed to detect a steady flame.
Your boiler has registered a critical internal safety lockout that requires a Gas Safe registered engineer to properly diagnose and reset.
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BoilerFaultCodes