The boiler tried to light but failed to detect a stable flame after several attempts, so it has locked out for safety.
Most common on: Logic, Logic+, Vogue
L2 is the most common Ideal fault code. It means the boiler went through its ignition sequence but the flame-sensing electrode did not detect a flame after the permitted number of attempts, so the control board closed the gas valve and locked the boiler out.
It is a deliberate safety lockout rather than a random error — the boiler will not keep sending gas when it cannot confirm the burner has lit. A one-off L2 usually clears with a single reset, but a boiler that locks out on L2 repeatedly has an underlying fault that needs a Gas Safe engineer.
Make sure a gas hob or another gas appliance lights. If nothing gets gas, the problem is the supply — check the gas cock at the meter is on and that a prepayment meter has credit.
The isolation lever under the boiler should be in line with the pipe (open). If it is turned across the pipe, the gas is shut off.
In cold weather the white plastic condensate pipe running outside can freeze and block, triggering a lockout. Thawing it gently with warm (not boiling) water can clear the fault.
Press and hold the reset button for a few seconds. If the boiler fires and stays lit, it was a one-off lockout. If L2 returns, stop resetting repeatedly.
Repeated L2 lockouts point to the electrode, gas valve, ignition leads or gas pressure — all of which need a Gas Safe registered engineer with the right test gear.
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 tried to light but failed to detect a stable flame after several attempts, so it has locked out for safety. L2 is the most common Ideal fault code. It means the boiler went through its ignition sequence but the flame-sensing electrode did not detect a flame after the permitted number of attempts, so the control board closed the gas valve and locked the boiler out.
You can try a single reset and the safe checks below, but Ideal L2 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 L2 means the underlying cause has not been fixed — most often no gas reaching the boiler (gas cock off, prepayment meter out of credit, or the wider supply interrupted). Resetting repeatedly will not solve it; get the boiler diagnosed properly.
Flame loss / no flame detected
Low water pressure
Fan speed / fan lockout fault
See all Ideal fault codes.