FH Low

Ferroli FH Fault Code

The Ferroli FH fault code means: your boiler is currently performing a brief automatic self-test to clear any trapped air from the system and will usually resume normal operation on its own after two minutes.. It appears on 3 Ferroli models in our database.

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.

Technical description: Air purge function (active for the first 120 seconds after ignition)

DIY fix possible

Wait for 120 seconds to allow the automated air purge cycle to complete.Do not turn off or reset the boiler while this light is displayed.If the code does not disappear after two minutes, check that your system pressure is at the correct level (typically 1-1.5 bar) and top it up if necessary.

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Ferroli models that show the FH fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ferroli FH fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026