High
Flashing LD2 on Biasi Riva Compact 24S

Your boiler has detected low water pressure or a circulation issue, preventing it from heating up to protect the system.

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

C.H. temperature / Primary circuit flow switch - Waiting for pressure/flow / Faulty C.H. temperature probe NTC / Faulty Primary circuit flow switch / Lack of water / Pump stuck / Air in the primary circuit

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 →LD3View →

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