E05 High

Keston E05 Fault Code

The Keston E05 fault code means: your boiler has stopped working because the internal fan, which safely exhausts fumes, is not spinning correctly or cannot be detected by the system.. It appears on 8 Keston models in our database.

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 failure – boiler cannot detect fan rotation – check fan operation and both connectors onto fan

What causes the Keston E05 fault?

This fault occurs when the boiler's control system loses communication with the fan or detects that it isn't spinning at the required speed. The most common reason is a mechanical failure of the fan motor or an electrical issue where the wires connecting the fan to the main circuit board have become loose or damaged.

Typical repair cost £250-£450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Keston models that show the E05 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Keston E05 fault code information on this page is sourced and cross-checked against the official Keston service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026