12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Thelia Condens
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Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler has lost the ability to accurately measure the temperature of the water used for your radiators, causing it to stop heating as a safety precaution.
Your boiler is having trouble communicating with its control panel, which prevents it from receiving accurate instructions to heat your home.
Your boiler's central control unit is experiencing an internal electronic failure and requires professional intervention to restore operation.
Your boiler has detected that the water inside the heating system has become dangerously hot and has shut itself down to prevent damage.
Your boiler is struggling to control its gas supply, which prevents it from safely igniting or maintaining a flame.
Your boiler has detected a problem with the internal mechanism that controls the gas supply, meaning it has shut down to keep your home safe.
Your boiler is failing to start because the electrical supply it is receiving from your home's wiring is too weak or unstable.
Your boiler's electronic display or control panel is having trouble communicating with the main system, causing the unit to stop operating.
Your boiler has lost its connection to the temperature sensor that monitors your heating water, so it has safely shut down to prevent overheating.
Your boiler's electronic control panel is not communicating correctly with the main internal system, preventing it from functioning.
Your boiler has detected that gases are not escaping properly through the flue, so it has safely shut itself down to prevent dangerous fumes from building up.
BoilerFaultCodes