Low
-ll- on Worcester Bosch Greenstar 35 CDi

Your boiler is performing a routine self-check and filling its internal safety drainage system after the power was turned off and back on.

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

The boiler runs for 15 minutes at minimum heating output to fill the condensate trap. This occurs every time the mains supply has been interrupted.

DIY fix possible

Wait 15 minutes for the cycle to complete automaticallyEnsure the boiler power remains switched onThe boiler will return to normal operation once the countdown finishes

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