High Lockout
HF on Ideal Mexico HE

Your boiler has detected a problem with the sensor that tracks the flame, meaning it cannot safely confirm if the gas is ignited and has shut down as a precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

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

Technical description

FLAME DETECTION - SHORT CIRCUIT ERROR

What causes this fault?

This fault occurs when the boiler's control system detects a continuous electrical signal from the flame sensor even when the gas should be turned off. The most common reason is a build-up of carbon or moisture causing an electrical short circuit on the electrode, or a fault within the internal wiring that tricks the boiler into thinking a flame is present.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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