High
4 red flashes on Baxi Assure

Your boiler's fan is not running or communicating correctly, preventing the system from safely clearing away exhaust fumes and starting the ignition process.

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

Fan fault

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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