BoilerFaultCodesECA 122 Fault Code
The ECA 122 fault code means: your boiler's secondary heating zone is not reaching the required temperature, meaning some of your radiators or underfloor heating may stay cold.. It appears on 1 ECA model in our database.
Technical description: Heating circuit 2 flow water temperature not reached
DIY fix possible
Check that all radiator valves in the second heating zone are fully openEnsure the zone valves or thermostats for that area are set to call for heatCheck if the boiler pressure is between 1.0 and 1.5 bar and top up if necessary
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ECA models that show the 122 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
ECA 122 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