Ferroli boiler fault codes
Ferroli make one distinction that is genuinely more useful than most manufacturers manage, and they state it at the head of their own fault tables. An A prefix means a permanent shutdown: the appliance has stopped and will stay stopped until somebody presses reset. An F prefix means a temporary shutdown that is reset automatically as soon as the value returns within the boiler's normal working range. So an F37 that appears and disappears is the appliance telling you the pressure is marginal, while an A01 is a hard lockout that needs intervention. Some faults escalate from one to the other, and Ferroli spell that out too: three F07 events inside twenty-four hours becomes an A04. There is a second thing to know before trusting any Ferroli code list, including this one. Ferroli reuse numbers across platforms with entirely different meanings — F07 is a flue gas overtemperature on the Optimax and T-One, an air pressure switch fault on the i25 and i29, and a PCB parameter fault on the FERcondens, all three published by Ferroli. Check which range you have before acting on a number.
Where the code shows on a Ferroli
Ferroli describe it like this: in the event of a problem the display flashes and a fault code appears, and when the boiler starts working normally again the display stops flashing and the code disappears. That is worth knowing because it means an F-prefix fault can come and go without anybody seeing it, so an appliance behaving oddly with nothing on the display is still worth investigating. What the older LED-only Ferroli appliances show is not something we can document — their literature is no longer published in a form we can read — so the codes here should not be read across to an appliance without a numeric display.
How to reset a Ferroli
One second. Ferroli print that figure in their own manuals and repeat it across ranges, and it is worth stating plainly because several repair sites tell you to hold the button for five to ten seconds. On a Ferroli the button is not only a reset: their own key calls it the Reset / Summer-Winter / OTC push button, and on the FERcondens a five-second hold is documented as the way into the OTC menu, where the heating curve and offset are set. So the duration is not a detail — a one-second press resets, and holding on can put you somewhere you did not mean to be. Only A-prefix faults need a reset at all; F-prefix faults clear on their own and pressing the button does nothing for them. Ferroli also publish their limit, and it is the shortest of any brand here: if the problem remains after two attempts at resetting, contact the Ferroli Service Centre. Not three, not five. Two.
Most common Ferroli faults
The Ferroli codes people look up most.
- A01Get it checkedThe burner failed to light and the appliance has locked out. Ferroli list a blocked siphon as a cause, which is worth checking early.
- F37Usually simple to fixSystem water pressure is outside the correct range. Because this is an F code it clears by itself once you top the system back up.
- A03Get it checkedHigh limit protection has operated. Ferroli point at circulation and at the flow sensor position, and both are worth checking.
- A05Get it checkedThe fan tachometer signal has been missing for an hour or more. The appliance has stopped and needs an engineer.
Every Ferroli fault code
6 published codes. Filtering happens in the page — every one is in the HTML.
Showing 6 of 6 codes
Ferroli models
Codes can differ between generations. Check yours.
Guides that help with Ferroli faults
Boiler fault codes explained: what they actually tell you
Codes look like diagnoses and are not. Understanding which family a code belongs to turns a meaningless number into a genuinely useful starting point.Read the guideHow to repressurise a boiler
The five-minute job that resolves more no-heating calls than any other. Here is how to do it properly, and how to tell when topping up is the wrong answer.Read the guideWhat a Gas Safe engineer actually checks in a boiler service
Most people pay for this once a year and stand in another room while it happens. Here is what should be going on, which test cannot be faked, and how to tell a real service from twenty minutes and an invoice.Read the guideWhat to do when your condensate pipe freezes
The single most common winter boiler fault, and one of the few you can genuinely fix yourself in fifteen minutes with a kettle and some patience.Read the guide
Looking for Ferroli’s own support? www.ferroli.co.uk. We are not affiliated with Ferroli.