11 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Promax SL
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Your boiler has detected that waste gases are not escaping correctly through the flue, so it has safely shut itself down to prevent harmful fumes from entering your home.
Your boiler has switched itself off for safety because it detected that it has become too hot to operate safely.
Your boiler has become too hot and has automatically switched itself off as a safety precaution.
Your boiler has shut down because it has either become too hot or detected that dangerous exhaust fumes are not escaping correctly through the chimney.
Your boiler has automatically shut down for safety because it has detected a blockage in the chimney or flue that prevents dangerous exhaust gases from escaping.
Your boiler has become too hot and has automatically switched itself off to prevent damage, meaning you currently have no heating or hot water.
Your boiler has sensed a problem with the dangerous exhaust gases escaping, so it has automatically shut itself down to keep your home safe.
Your boiler has become too hot and has automatically shut itself down as a safety precaution.
Your boiler has detected that fumes are not escaping properly through the flue and has shut itself down for your safety.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected potentially dangerous exhaust fumes backing up into your home due to a blocked or obstructed chimney or flue, and has safely shut itself off to prevent carbon monoxide poisoning.
BoilerFaultCodes