High
Red L.E.D. H on Ariston Excalibur

Your boiler has switched itself off because the water inside the heat exchanger 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. In the event that the safety limit is exceeded for the temperature of the water in the boilers exchanger, the thermostat shuts off the boiler and the red L.E.D. H illuminates.

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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Red L.E.D. DView →

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