Low
FH on Ferroli Optimax HE Plus

Your boiler is currently performing an automatic two-minute process to clear air from the system before it fires up.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Air purge function (first 120 seconds)

Shared across the Optimax HE Plus range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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

Wait 120 seconds for the cycle to finishMonitor the display to see if it automatically switches to a temperature readingIf the code persists after 5 minutes, turn the power off at the fused spur for 30 seconds and turn it back on to reset

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Related fault codes

F37View →

All 22 fault codes on the Optimax HE Plus

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

A01A02A03A04A05A06A47F07F10F11F12F13F14F15F34F35F37F39F42Low system pressureNo burner ignition

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