30 High

Unical 30 Fault Code

The Unical 30 fault code means: your boiler's internal computer settings have been disrupted by nearby electrical interference and need to be reset to work correctly.. 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: SERVICE PARAMETERS Service parameters altered due to possible electromagnetic interferences.
Typical repair cost £100-280 (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 30 fault code

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

Source

Unical 30 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