How much does it cost to fix Biasi error code E00---688?

Typical repair cost for the Biasi E00---688 fault is £90-160 including labour.

E00---688 High

Biasi E00---688 Fault Code

Q: What does the Biasi E00---688 fault code mean?

Your boiler has detected that water isn't moving through the system properly, meaning it won't fire up to provide heating or hot water until the internal pressure sensor is triggered.

Also written as E00688 — same fault.

The Biasi E00---688 fault code means: your boiler has detected that water isn't moving through the system properly, meaning it won't fire up to provide heating or hot water until the internal pressure sensor is triggered.. It appears on 1 Biasi model in our database.

Technical description: Main flow switch membrane

Typical repair cost £90-160 (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 E00---688 fault code

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

Riva Compact 24S Repair: £90-160

Source

Biasi E00---688 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