High
A05 on Ferroli Bluehelix Tech

Your boiler has stopped working because the internal fan, which safely removes waste gases, is not spinning at the correct speed.

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 error

From this model's manual
Verified against the Ferroli Bluehelix Tech installation & service manual, page 43.
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 board cannot detect that the fan is spinning at the required speed to safely clear exhaust gases. The most common reason is a mechanical failure within the fan motor or a communication issue caused by a damaged wiring harness or a fault on the main 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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