26 High

Unical 26 Fault Code

The Unical 26 fault code means: your boiler has shut down because the internal fan is spinning faster than it is supposed to, which prevents the system from safely managing the gas flame.. It appears on 2 Unical 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: SPEED OUT OF CONTROL Alteration of the fan speed; the speed is above that requested
Typical repair cost £180-380 (including labour)

Engineer required

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

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Unical models that show the 26 fault code

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

Source

Unical 26 fault code information on this page is sourced and cross-checked against the official Unical service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026