High
E.04 – .17 on Baxi Netaheat

Your boiler has detected a serious issue with the gas flow or the unit that mixes gas and air, preventing it from firing up safely.

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

Permanent fault. Problem with gas valve or defective gas/air unit.

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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