High
LD1, LD2, LD3 Flashing on Biasi Riva Compact 24S

Your boiler has detected a problem with the internal temperature sensor that monitors the heating water, preventing the unit from operating correctly.

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

Faulty C.H. temperature probe NTC in D.H.W. only models (SR models)

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

LD1View →LD2View →LD3View →

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