No flash Low

Worcester Bosch No flash Fault Code

Also written as NOFLASH — same fault.

The Worcester Bosch No flash fault code means: your boiler is undergoing a standard restart process because the reset button was held down, and it will return to normal operation shortly.. It appears on 1 Worcester Bosch model in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Reset button pressed by mistake.

DIY fix possible

Wait for 30-60 seconds for the boiler to complete its internal startup checks.Ensure any 'Reset' light has stopped flashing.Check if the display returns to showing the current temperature or 'P' status.

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Worcester Bosch models that show the No flash fault code

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

Source

Worcester Bosch No flash 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