Viessmann D6 Error | Official & Hot

UK prices similar in GBP; always verify with a local engineer.

Ensure your system pressure is in the "green zone," typically between 1 and 1.5 bar Viessmann Pressure Guide to learn how to top up your system if it's low. Bleed Your Radiators: viessmann d6 error

If your Viessmann boiler is showing a D6 error, it usually indicates a flame failure or ignition problem. That can mean the burner is not lighting, the flame is being lost during operation, or the ignition sequence is interrupted. Below is a concise guide to diagnosing, troubleshooting, and when to call a pro. UK prices similar in GBP; always verify with

If the above steps do not resolve the D6 error after 15 minutes of runtime, . The issue is likely a failed BCU or display module, requiring a Gas Safe registered engineer (UK) or licensed HVAC technician (US/Canada). That can mean the burner is not lighting,

Loose or corroded cables between the fan and the main control board (PCB) can disrupt signals.

Try a simple power cycle: