High
E.04 – .17 on Baxi Suprima 70

Your boiler has detected a serious internal communication or hardware failure within the gas management system and has locked itself out for safety.

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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