High
E3 on Remeha Gas 610 Eco Pro

Your boiler has switched itself off because it has reached a temperature that is too high, often caused by a circulation problem or a blockage.

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

High limit thermostat (STB) has operated

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

E1View →

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