High Lockout
E.04 – .17 on Baxi 200 Combi (range)

Your boiler has detected a serious problem with its internal gas system and has shut down 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

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

What causes this fault?

This fault occurs when the boiler's control board detects an electrical or mechanical failure within the internal gas delivery system. The most common reason is a malfunctioning gas valve that can no longer open or close correctly, or a communication error between the valve and the main circuit board. To ensure your safety, the boiler automatically shuts down because it cannot accurately control the flow of fuel to the burner.

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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