High
50-60-70 (ll-ll-ll) on Ariston Clas HE 35

Your boiler's temperature sensor is providing an incorrect signal, causing the system to stop heating for safety reasons.

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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