High
E18 on Biasi Antares Combi

Your boiler has detected that the water returning from your radiators is getting too hot, which often points to a circulation problem or a faulty sensor.

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

Heating return NTC probe overtemperature

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

E05View →E17View →E19View →

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