Er 02 High

Biasi Er 02 Fault Code

Also written as ER02 — same fault.

The Biasi Er 02 fault code means: your boiler has switched itself off because it has detected that the water inside has become or is becoming too hot.. It appears on 2 Biasi models in our database.

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: Safety thermostat intervention lockout
Typical repair cost £100-280 (including labour)

DIY fix possible

Ensure all radiator valves are fully open to allow water to circulateCheck that the boiler pressure is between 1.0 and 1.5 bar on the gaugePress and hold the 'Reset' button for five seconds to restart the system

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Biasi models that show the Er 02 fault code

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

Source

Biasi Er 02 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 7 July 2026