How much does it cost to fix Biasi error code E01---204?

Typical repair cost for the Biasi E01---204 fault is £180-£350 including labour.

E01---204 High

Biasi E01---204 Fault Code

Q: What does the Biasi E01---204 fault code mean?

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.

Also written as E01204 — same fault.

The Biasi E01---204 fault code means: 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.. It appears on 1 Biasi model in our database.

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

Typical repair cost £180-£350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Biasi models that show the E01---204 fault code

Click a model for the full fault code list and model-specific repair notes.

Riva Compact 24S Repair: £180-£350

Source

Biasi E01---204 fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026