High
E01---204 on Biasi Riva Compact 24S

Your boiler has detected a problem with the internal part that heats your water, often caused by a blockage or a faulty sensor, meaning you will likely have no hot water.

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

D.h.w. heat exchanger (M96.24SM/...)

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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