E12 High

ECA E12 Fault Code

The ECA E12 fault code means: your boiler's computer memory has suffered an internal error, meaning the main control board can no longer process the instructions needed to run the system.. It appears on 1 ECA model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: EEPROM failure (internal memory error)
Typical repair cost £220-380 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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ECA models that show the E12 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

ECA E12 fault code information on this page is sourced and cross-checked against the official ECA service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026