How much does it cost to fix boiler error code 18E?

Typical repair cost for the boiler 18E fault is £80-150 including labour.

18E High

Boiler Fault Code 18E

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code 18E appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected that there is not enough water circulating inside the system to operate safely. (As reported on Biasi Concept 400 20 1 Mfs)

Pick your boiler brand for the 18E fix

Biasi 18E 1 model

Source

Information for the 18E 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 7 July 2026