The boiler has lost or cannot detect the flame while running, so it has shut the gas off.
Most common on: Logic, Logic+, Vogue
F2 means the flame-detection circuit has lost the flame signal — either the burner failed to stay lit or the boiler could not sense the flame in the first place. Where L2 is the lockout after repeated failed ignition attempts, F2 is more specifically the flame-loss condition itself.
As with any flame fault it is a safety measure: the boiler will not hold the gas valve open when it cannot confirm a flame. The underlying causes overlap heavily with L2, so the two often appear together on the same boiler.
Check other gas appliances light, the boiler gas cock is open and any prepayment meter has credit.
In freezing weather, thaw the external condensate pipe if it is iced up or blocked, then try again.
Hold the reset button. If the boiler fires and runs normally, it may have been a transient loss. If F2 returns, do not keep resetting.
A recurring F2 needs a Gas Safe engineer to clean or replace the electrode and test the gas valve, leads and PCB.
Work on the gas side of a boiler must be carried out by a Gas Safe registered engineer. The checks above are limited to safe, non-invasive things a homeowner can look at (pressure, resets, the gas supply) — if in doubt, stop and call an engineer.
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The boiler has lost or cannot detect the flame while running, so it has shut the gas off. F2 means the flame-detection circuit has lost the flame signal — either the burner failed to stay lit or the boiler could not sense the flame in the first place. Where L2 is the lockout after repeated failed ignition attempts, F2 is more specifically the flame-loss condition itself.
You can try a single reset and the safe checks below, but Ideal F2 usually needs a Gas Safe registered engineer. Never work on the gas side of a boiler yourself — it is illegal and dangerous unless you are Gas Safe registered.
A recurring F2 means the underlying cause has not been fixed — most often interrupted or low gas supply. Resetting repeatedly will not solve it; get the boiler diagnosed properly.
See all Ideal fault codes.