How much does it cost to fix boiler error code T3?

Typical repair cost for the boiler T3 fault is £0-80 including labour.

T3 Low

Boiler Fault Code T3

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code T3 appears across 1 boiler brand and 11 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is performing a routine check of its internal pump and may temporarily pause normal operation while it completes the test. (As reported on Worcester Bosch Greenstar Si Combi / i System)

Pick your boiler brand for the T3 fix

Worcester Bosch T3 11 models

Source

Information for the T3 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

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