Ferroli Optimax HE Plus fault codes
Built 2008 onwards
Long-running range including the 31c and 38c. Two manuals from it are readable and they are the clearest published source for the Ferroli code set, so most of what is on these pages is checked against them. Note that the HE 31 C and the HE PLUS 31c/38c do not agree on everything: the low-voltage threshold is 180V on one and 170V on the other, and only the HE 31 C publishes the 95°C figure for a flue gas overtemperature and a separate F40 for high pressure.
Codes on the Optimax HE Plus follow the same Ferroli scheme as the rest of the range. Where a code behaves differently on this generation, the code page says so.
Ferroli fault codes
Every published Ferroli code. Open a code to see which models and years it applies to.
- A01The burner failed to light and the appliance has locked out. Ferroli list a blocked siphon as a cause, which is worth checking early.Get it checked
- F37System water pressure is outside the correct range. Because this is an F code it clears by itself once you top the system back up.Usually simple to fix
- A03High limit protection has operated. Ferroli point at circulation and at the flow sensor position, and both are worth checking.Get it checked
- A05The fan tachometer signal has been missing for an hour or more. The appliance has stopped and needs an engineer.Get it checked
- A02A flame is being detected while the burner should be off. Switch the appliance off and get a Gas Safe engineer to it.Stop — call an engineer
- F07Flue gas temperature has stayed above 95°C for more than two minutes. Three of these in a day becomes a permanent A04 lockout.Get it checked