Low Lockout
Fd on Worcester Bosch Greenstar i

Your boiler has stopped because the reset button was held down for too long or pressed by mistake, causing a minor software confusion.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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. Press reset button again.

What causes this fault?

This fault occurs when the boiler's control board detects that the reset button has been held down for more than 15 seconds. It is usually caused by a user accidentally leaning on the button or pressing it for too long while trying to clear a previous error. This puts the software into a temporary state of confusion, causing it to shut down as a safety precaution.

DIY fix possible

Press the reset button briefly (less than one second).Wait for the display to clear and the boiler to restart.Ensure no other fault codes are appearing once the 'Fd' clears.

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