Low Lockout
Fd on Worcester Bosch Greenstar CDi Compact

Your boiler's reset button has been pressed incorrectly or held down for too long, causing a temporary communication error.

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

Mains power error - Electrical power interruption

What causes this fault?

This fault occurs when the boiler's reset button is held down for too long or pressed repeatedly in a short space of time. The internal control board interprets this continuous signal as a communication error rather than a legitimate request to restart. It effectively puts the system into a temporary state of confusion until the button is released and the board can reset itself.

DIY fix possible

Press the reset button again firmly once.Wait up to 30 seconds for the display to clear.Restart the boiler using the power switch if the code persists.

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