Low
II - on Worcester Bosch Greenstar i

Your boiler is performing a routine initial safety check to fill its internal drainage system after the power was recently switched off.

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.

What the manual says

Manufacturer manual

Boiler running for 15 minutes at minimum heating output to fill the condensate trap (alternates with central heating flow temperature). This occurs if the mains supply has been interrupted.

From this model's manual
Verified against the Worcester Bosch Greenstar I installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for 15 minutes for the cycle to complete automaticallyEnsure your heating or hot water controls are set to 'on'The code will disappear and be replaced by the temperature once finished

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