How much does it cost to fix Biasi error code Faulty primary circuit?

Typical repair cost for the Biasi Faulty primary circuit fault is £100-£250 including labour.

Faulty primary circuit High

Biasi Faulty primary circuit Fault Code

Q: What does the Biasi Faulty primary circuit fault code mean?

Your boiler has lost water pressure or the water isn't moving through the system properly, which has triggered a safety shutdown to prevent overheating.

Also written as FAULTYPRIMARYCIRCUIT — same fault.

The Biasi Faulty primary circuit fault code means: your boiler has lost water pressure or the water isn't moving through the system properly, which has triggered a safety shutdown to prevent overheating.. It appears on 1 Biasi model in our database.

Technical description: No water or absence of flow

Typical repair cost £100-£250 (including labour)

DIY fix possible

Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is low, use the filling loop valves underneath the boiler to top it up.Ensure all radiator valves and lockdowns are open to allow water to flow.Restart the boiler once the correct pressure is reached.

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Biasi models that show the Faulty primary circuit fault code

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

Riva Compact 24S Repair: £100-£250

Source

Biasi Faulty primary circuit 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