High
Overheat lockout indicator on Halstead Eden CBX/SBX

Your boiler has automatically turned itself off because it reached a dangerously high temperature to prevent damage.

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

Indicates the overheat cut off device has operated; requires reset.

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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Related fault codes

E01View →E04View →

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