Medium
bC on Viessmann Vitodens 300-W

Your boiler has lost its connection with the remote control thermostat for your main heating circuit, meaning it cannot receive instructions on when to turn the heating on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Control mode without remote control: Communication fault - Vitotrol remote control heating circuit A1

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W 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.

DIY fix possible

Check if the batteries in your Vitotrol remote control unit need replacing.Ensure the remote control is properly docked on its wall bracket or base station.Restart the boiler using the power switch to try and refresh the communication link.

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Related fault codes

bAView →bdView →C2View →

All 60 fault codes on the Vitodens 300-W

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

0F9A9b9C9F101820283038404850515858:05980:092939497:2A2:0A7b0b1b4b5b7b8bAbdbEbFC2C5C6C7CdCECFdAdbdEE4E5E6F0F1F2F3F4F7F8F9FAFdFE

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