High Lockout
L8 on Ideal Esprit HE

Your boiler has detected an internal communication error between its electronic control boards or a software fault.

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

ALTERNATING 'L' '8' GO TO FRAME 89

What causes this fault?

This fault occurs when the main control board and the display panel stop talking to each other effectively. It is usually caused by a loose wiring connection between the two components or a critical failure of the internal software on the main circuit board. Without this constant stream of data, the boiler shuts down as a safety precaution because it can no longer monitor its own operations.

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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