Blue light High

Worcester Bosch Blue light Fault Code

Also written as BLUELIGHT — same fault.

The Worcester Bosch Blue light fault code means: your boiler has stopped working for safety reasons and is waiting for you to manually restart it to try and clear the fault.. It appears on 2 Worcester Bosch models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Lockout reset
Typical repair cost £100-250 (including labour)

DIY fix possible

Locate the blue 'Reset' button on the boiler control panel.Press and hold the reset button for approximately 3 seconds.Observe if the boiler ignites and the blue light stops flashing.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Worcester Bosch models that show the Blue light fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch Blue light 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