High Lockout
E.04 – .00 on Baxi 200 Combi (range)

Your boiler has lost communication with the internal gas control system, meaning it cannot safely release fuel to create a flame.

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

Gas valve error – gas valve not detected.

What causes this fault?

This fault occurs when the boiler's central brain loses its electronic connection with the gas valve, which is the component responsible for letting fuel into the burner. The most common reason is a loose or damaged wiring connection between these two parts, or an internal electronic failure within the gas valve 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.

Find a Gas Safe engineer
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