Medium
F40 on ECA Proteus Premix 24 HCH

Your boiler has temporarily stopped working because the water pressure inside the system has risen higher than it should be.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

High Water Pressure Fault

From this model's manual
Verified against the Eca/Eca Proteus Premix 24 Hch installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the filling loop valves beneath your boiler and ensure they are fully closed.Bleed one or two of your radiators slightly using a radiator key to release excess water and pressure.Check the boiler pressure gauge until it drops back down into the normal green zone (usually between 1 and 1.5 bar).

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Related fault codes

F37View →F38View →

All 28 fault codes on the Proteus Premix 24 HCH

Seeing a different code? Every code this model can display, in one place.

E01E02E03E05E08E09E12E15E16E17E18E21E33E35E80E82F07F13F34F37F39F47F50F51F52F53F81

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