High
LD1, LD2, LD3 Flashing on Biasi Riva Compact 24S (M90E.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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Riva Compact He C2 Service 2007 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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