High
2 green flashes on Baxi 400 Heat

Your boiler has paused because a safety switch or an external control has told it to stop running temporarily.

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.

What the manual says

Manufacturer manual

Shutdown Input warning

From this model's manual
Verified against the P3 Baxi 400 Heat installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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

1 green flashView →E160View →

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