High
F2 on Saunier Duval Xeon 120 FF

Your boiler has stopped working because an internal safety fuse has blown, preventing the electronic control system from powering up.

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.

What the manual says

Manufacturer manual

PCB Fuse (F1A). Before using the fault finding chart ensure all wiring is correct and in good condition, the pump is not faulty and check the PCB fuse F2

From this model's manual
Verified against the Saunier Duval Xeon 120 Ff installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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