E21 + RESET High

Biasi E21 + RESET Fault Code

Also written as E21RESET — same fault.

The Biasi E21 + RESET fault code means: your boiler has failed to ignite and has locked itself out for safety, meaning you will have no heating or hot water until it is reset or repaired.. It appears on 1 Biasi model 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: Lockout EVG
Typical repair cost £120-£350 (including labour)

DIY fix possible

Press and hold the 'Reset' button on the control panel for five seconds.Check that your gas supply is active (e.g., check other gas appliances like a hob).Ensure your prepaid gas meter has sufficient credit.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Biasi models that show the E21 + RESET fault code

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

Source

Biasi E21 + RESET 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