High
6 10 on Ariston Clas HE 28

Your boiler has detected a break in a safety circuit designed to shut the system down if it overheats, which has caused it to stop working completely.

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

Thermofuse open

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

6 12View →

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