Medium
F41 on Ferroli Optimax HE 31 C

Your boiler has temporarily stopped working because the water pressure inside the system has risen too high.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

System pressure too high

From this model's manual
Verified against the Ferroli/Ferroli Optimax He 31 C 4726742 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 connected to your boiler.Ensure both filling loop valves are completely closed and not letting extra water in.Bleed one or two radiators in your home to release a small amount of water and lower the pressure gauge to between 1 and 1.5 bar.

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Related fault codes

F37View →F39View →

All 32 fault codes on the Optimax HE 31 C

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

A01A02A03A04A05A06A41F04F05F07F10F11F12F13F14F15F20F21F24F34F35F37F39F40F42F43F47F50F51Low system pressureNo burner ignition

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