Low
fl- on Worcester Bosch Greenstar R29 40 HE

Your boiler is performing a routine initial startup procedure to fill its internal condensation trap and is not actually experiencing a fault.

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, the display (K) alternates between 'fI-' and the flow temperature.

DIY fix possible

Wait 15 minutes for the automated cycle to completeEnsure the boiler power remains on during this periodObserve the display until the code disappears and the normal temperature is shown

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