High Lockout
L.......A........ on Ideal Esprit HE

Your boiler has shut down because it has detected it is getting too hot, usually due to a lack of water circulation or a blockage in the system.

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

OVERHEAT ERROR

What causes this fault?

This fault occurs when the water inside the boiler exceeds a safe temperature limit, causing the safety sensors to shut the system down to prevent damage. The most common reasons are a failed internal pump that isn't moving the water away fast enough or a buildup of sludge and debris creating a blockage in the heat exchanger.

This issue often appears when the heating is first turned on after summer, as pump components can seize up after months of inactivity.

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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