High
40-60 (ll-ll) on Ariston Clas HE 28

Your boiler has lost its connection to its internal control system or has blown an electrical safety fuse, meaning it cannot operate safely.

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

Wiring problem (or fuse 1.25 A)

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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