18 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Glen Dimplex / Halstead Eden CB
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Your boiler has temporarily shut down because the internal temperature got too high, which is a safety feature to prevent damage.
Your boiler has detected an internal sensor or safety check failure and has safely locked itself out to prevent unsafe operation.
Your boiler is trying to start up and light the flame, but it is failing to ignite after five attempts and has safely locked itself out.
Your boiler has sensed that the exhaust gases are becoming too hot, causing it to shut down automatically for your safety.
Your boiler has shut down because a temperature sensor is faulty or the main unit has become too hot to operate safely.
Your boiler is detecting a potential issue where the gas supply valve may not be closing properly when your heating turns off.
Your boiler has stopped working because its internal fan isn't spinning at the correct speed or the system cannot detect that it is running.
Your boiler has stopped working because its internal computer or the burner has encountered a serious communication error.
Your boiler's computer needs to be officially 'told' that a new electronic control part has been installed before it will allow the system to ignite.
Your boiler has failed to detect a flame or has registered a new control component, meaning it has temporarily locked out for safety and stopped providing heating and hot water.
Your boiler has lost its connection to its internal memory chip or cannot detect a flame, meaning it cannot operate safely.
Your boiler has failed to ignite or stay lit because it cannot detect that the internal fan is running correctly to safely clear gases.
Your boiler has stopped working because it has detected a safety system or internal computer error, meaning it cannot safely ignite.
Your boiler has stopped working because it cannot detect enough water flowing through the system.
Your boiler briefly lights its flame before turning itself off again because it detects an issue with how the heat is being measured inside.
Your boiler is struggling to operate because the electrical supply is unstable or too low, preventing the flame from starting safely.
Your boiler's internal computer has detected a fault in its own safety monitoring system and has shut down to keep you safe.
Your boiler has stopped because it cannot detect enough water moving through the system to heat safely.
BoilerFaultCodes