12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Greenstar CDi Classic ErP
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Your boiler has detected that the internal water pump is not working properly, which usually happens because it is stuck or has run without water.
Your boiler is struggling to accurately measure your hot water temperature because one of its internal sensors has stopped working properly.
Your boiler has lost its connection to its external thermostat or control unit, meaning it cannot properly receive instructions to turn the heating on.
Your boiler has temporarily lost communication with an internal electronic identification chip, meaning it cannot safely start up.
Your boiler has detected that the internal fan responsible for safely pushing out exhaust gases is not spinning fast enough.
Your boiler has temporarily stopped working because it cannot accurately read the temperature of the water flowing through your heating system.
Your boiler has temporarily shut down because the internal water temperature reached an unsafe limit.
Your boiler has fired up, but it cannot detect a steady flame to keep itself running safely, so it has temporarily locked out to prevent any unburnt gas from building up.
Your boiler has detected an internal computer error and has safely shut itself down to prevent any further issues.
Your boiler is confused because it senses a flame inside even though it has been told to turn off.
Your boiler has sensed that a flame is still present inside even after the gas supply has been turned off, which triggers a safety lock.
Your boiler's reset button was accidentally pressed too many times, and it just needs a few moments to clear the error.
BoilerFaultCodes