Low
FH on Ferroli Extrema C

Your boiler has started an automatic process to remove trapped air from the system which usually happens after it has been turned on or serviced.

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

Heating system air venting cycle

From this model's manual
Verified against the Ferroli Extrema C 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

Wait for the cycle to finish, which typically takes about 10 to 15 minutes.Do not turn the boiler off during this time as it is functioning normally.If the code does not clear after 20 minutes, turn the boiler off at the mains for one minute and turn it back on.

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