High
0b on Viessmann Vitodens 100 Compact

Your boiler has detected that water is not flowing through it properly, which is likely because there is trapped air in the system or a sensor is misreading the flow.

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

Flow of water too low. Air in heat exchanger. Flow switch faulty.

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 100 Wb1a 13kw 18kw 24kw Compact Heat Only Installation Servicing Instructions Manual 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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All 19 fault codes on the Vitodens 100 Compact

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

30386068b1b5E4E5F0F2F3F4F5F8F9FAFdFE

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