How much does it cost to fix boiler error code b26?

Typical repair cost for the boiler b26 fault is £80-140 including labour.

b26 High

Boiler Fault Code b26

Also written as B26 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code b26 appears across 4 boiler brands and 8 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has stopped working because the waste water pipe or trap is full and cannot drain away properly. (As reported on Vokera Pinnacle)

Pick your boiler brand for the b26 fix

Atag b26 1 model Johnson Starley b26 4 models Remeha b26 2 models Vokera b26 1 model

Source

Information for the b26 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