High
FC on Viessmann Vitodens 100-W BPJA 21kW P25

Your boiler has shut itself down as a safety precaution because its burner or fan isn't working correctly, so it may not be providing heating or hot water until a qualified engineer checks it.

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

Burner blocked. Electrical fan control (control unit) faulty

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 100 W Bpja 5609913 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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Related fault codes

F4View →F5View →F7View →

All 21 fault codes on the Vitodens 100-W BPJA 21kW P25

Seeing a different code? Every code this model can display, in one place.

5A3038515259b0b8E3E5F0F1F2F3F4F8F9FAFdFF

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