Low
t - on Worcester Bosch Greenstar i

Your boiler is simply reheating its internal hot water tank because the power was recently turned off and then 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.

What the manual says

Manufacturer manual

Heating the internal DHW tank (alternates with -I-). 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 approximately 15 to 30 minutes for the boiler to finish the reheating cycle.Check that your heating and hot water controls are set to their normal positions.If the code persists for over an hour, try restarting the boiler using the reset button.

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