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

Your boiler has stopped working because one of its internal temperature sensors is providing an inaccurate reading, causing the system to shut down for safety.

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

Centralheating return 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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