High
E01---205 on Biasi Riva Compact 24S (M90E.24S)

Your boiler is failing to heat your tap water correctly because the internal heat exchanger is likely blocked or faulty.

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

D.h.w. heat exchanger (M96.28SM/...)

From this model's manual
Verified against the Biasi Riva Compact 24s 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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