t - Low

Worcester Bosch t - Fault Code

Also written as T — same fault.

The Worcester Bosch t - fault code means: your boiler is simply reheating its internal hot water tank because the power was recently turned off and then back on.. It appears on 1 Worcester Bosch model in our database.

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: Heating the internal DHW tank (alternates with -I-). This occurs if the mains supply has been interrupted.

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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Worcester Bosch models that show the t - fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch t - fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026