How much does it cost to fix boiler error code 336?

Typical repair cost for the boiler 336 fault is £120-250 including labour.

336 High

Boiler Fault Code 336

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code 336 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 lost communication with an external accessory or sensor, causing it to stop operating because it cannot confirm the system's status. (As reported on ECA FELiS FL 50 HM)

Pick your boiler brand for the 336 fix

ECA 336 1 model

Source

Information for the 336 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