A15 High

Ferroli A15 Fault Code

The Ferroli A15 fault code means: your boiler is struggling to clear exhaust gases because it cannot confirm that the internal fan is moving air properly, so it has shut down for safety.. It appears on 4 Ferroli 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: Air pressure switch (fails to close contacts within 20 sec. of fan activation)
Typical repair cost £150-250 (including labour)

Engineer required

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

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Ferroli models that show the A15 fault code

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

Source

Ferroli A15 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

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