How much does it cost to fix boiler error code 40 50 80?

Typical repair cost for the boiler 40 50 80 fault is £120-220 including labour.

40 50 80 High

Boiler Fault Code 40 50 80

Also written as 405080 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 40 50 80 appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has lost the ability to measure the temperature of the water being stored for your taps, which prevents it from heating your hot water correctly. (As reported on Chaffoteaux Serelia 24 MFFI)

Pick your boiler brand for the 40 50 80 fix

Chaffoteaux 40 50 80 2 models

Source

Information for the 40 50 80 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