High
Red L.E.D. G on Ariston Euro Prisma 24

Your boiler has switched itself off because it has become too hot to 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

SHUTDOWN DUE TO OVERHEATING. This anomaly is signalled by the red “G” L.E.D. The boiler shuts off because the safety thermostat detected that the boiler temperature has reached the temperature limit.

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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