High
Section D on Baxi System

Your boiler has detected a failure in one of its internal safety sensors or the fan, meaning it cannot circulate water or vent gases safely and has stopped working.

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

No continuity across flow microswitch, primary temperature sensor faulty, or fan failure

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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