High
50-60-80 (ll-ll-ll) on Ariston Clas HE 28

Your boiler has lost its ability to measure the temperature of the water used for your radiators, so it has shut down as a precaution to prevent overheating.

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 (open 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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Related fault codes

1 01View →1 02View →1 03View →

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