High Lockout
H......F........ on Ideal Esprit HE

Your boiler has detected an electrical fault with the sensor that confirms the flame is lit, preventing it from firing up for your safety.

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 receives a signal that a flame is present before it has even tried to light. The most common reason is a build-up of carbon or moisture on the sensing probe which creates an accidental electrical path, or a damaged wire touching the boiler casing.

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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