High
E08 on Ariston Challenger 80E

Your boiler has switched off because a safety sensor in your underfloor heating system has detected the water is getting too hot and has triggered an automatic shutdown to prevent damage.

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

Under floor heating system safety thermostat contact open (boiler shutdown both in D.H.W. mode and C.H. mode; boiler operation resumes automatically when the thermostat contact closes on cooling).

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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