Emergency
F40 on ECA Confeo Premix HM

Your boiler has shut down because there is too much water in the system, causing the pressure to rise above a safe limit.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Eca Confeo Premix Hm installation & service manual, page 43.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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