BoilerFaultCodesECA F40 Fault Code
The ECA F40 fault code means: your boiler has shut down because the internal water pressure has risen too high, likely due to overfilling or a valve being left open.. It appears on 4 ECA models in our database.
Technical description: High Water Pressure Fault (blocking) — water pressure sensor detects high water pressure (2.9 bar); check water pressure; turn off device and restart; if persists notify ECA authorised service
DIY fix possible
Check that the filling loop valves under the boiler are fully closed.Bleed water from a radiator using a bleed key to lower the system pressure.Monitor the pressure gauge until it returns to between 1.0 and 1.5 bar.Restart the boiler using the reset button.
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ECA models that show the F40 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
ECA F40 fault code information on this page is sourced and cross-checked against the official ECA service / installation manuals for each affected model.
- ECA Confeo Premix HCH manual (PDF)
- ECA Confeo Premix HM manual (PDF)
- ECA Confeo Premix HST manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026