High
50-60 (ll-ll) on Ariston Clas HE 24

Your boiler has lost the ability to read the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.

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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