BoilerFaultCodes.com
L0C High Lockout

Your boiler has been manually reset too many times in a short window of time and has locked itself out as a safety precaution.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: 5 Boiler Resets in 15 minutes

What causes this fault?

This fault occurs when the reset button has been pressed more than five times within a fifteen-minute window. It is usually triggered because a homeowner is trying to clear a persistent underlying error, such as a flame failure or ignition problem, and the internal computer has locked the system down for safety. The boiler enters this state to prevent potential damage from repeated failed start-up attempts.

Typical repair cost £0-120 (including labour)

DIY fix possible

Turn the power to the boiler off at the fused spur switch (the wall switch).Wait for at least 5 minutes to allow the internal timer to reset.Turn the power back on and wait for the boiler to complete its start-up sequence without pressing the reset button.

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