Emergency
FC on Viessmann Vitodens 200-W B2HA-30

Your boiler has shut itself down as a safety precaution because part of its gas supply or exhaust route isn't working properly, so it needs a qualified engineer to check it before it's used again.

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Gas train faulty, faulty modulation valve control or flue gas path blocked

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2ha B2ka 5772909 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 emergency 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

All 83 fault codes on the Vitodens 200-W B2HA-30

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

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