High Lockout
E0 on Baxi Avanta

Your boiler has detected a problem with one of its temperature sensors and has stopped working as a safety precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Temperature sensor fault

What causes this fault?

This fault occurs when the boiler's internal computer loses communication with one of the probes that monitors water temperature. The most common reason is that the sensor has physically failed or 'drifted' out of range, meaning it can no longer provide an accurate reading. In some cases, the issue is caused by loose electrical connections or a fault within the main control board itself.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E1View →E2View →E3View →

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