High
Safety thermostat lockout on Biasi Riva Advance M96.24SM

Your boiler has switched itself off to prevent overheating, likely due to a circulation issue or a component getting too hot.

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

Lockout condition triggered by the safety thermostat.

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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