High
50-60-70 (ll-ll-ll) on Ariston Genus 30 Plus

Your boiler has stopped working because a sensor that measures the temperature of the water circulating to your radiators is sending an incorrect signal, causing a safety shutdown.

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

Central heating flow thermistor faulty (short circuit)

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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