High
4 red flashes on Baxi EcoBlue System

Your boiler's fan is not spinning or communicating correctly with the system, preventing the boiler from starting safely.

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

Fan fault

From this model's manual
This code was read directly from the manufacturer service manual for this model.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's control system detects that the fan is not spinning at the required speed to safely clear exhaust gases. The most common reasons are a mechanical failure of the fan motor, a buildup of debris blocking the blades, or a communication error caused by a faulty circuit board.

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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