BoilerFaultCodesWorcester Bosch Blue indicator light off Fault Code
Also written as BLUEINDICATORLIGHTOFF — same fault.
The Worcester Bosch Blue indicator light off fault code means: your boiler has no power and is completely switched off, meaning you have no heating or hot water until the electrical supply is restored.. It appears on 2 Worcester Bosch models in our database.
Technical description: The appliance is switched off via the master switch or there is no power supply to the appliance.
DIY fix possible
Check that the main boiler power switch (usually a fused spur near the boiler) is turned to the ON position.Ensure the master dial on the boiler control panel is not set to the 'Off' position.Check your home's main consumer unit (fuse box) to see if a circuit breaker has tripped or a fuse has blown.
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Gas Safe Register →Worcester Bosch models that show the Blue indicator light off fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch Blue indicator light off fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026