High
F.xx on Heatline Capriz 2

Your boiler has encountered a technical communication or internal sensor error that prevents it from firing up correctly.

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.

Technical description

Fault code (specific code depends on the number shown in place of xx), contact a competent person.

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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