Verify fan and air supply

A: No. D6 is a hard lockout. The boiler will not fire at all.

or a Viessmann-trained technician. Professional intervention is necessary if: How to reset a Viessmann boiler

Sudden power cuts, brownouts, or a faulty earthing in your home’s electrical system can confuse the boiler’s electronics, triggering D6.

The exact meaning of the d6 code depends on the type of Viessmann unit you own:

Viessmann D6 Error [hot] -

Verify fan and air supply

A: No. D6 is a hard lockout. The boiler will not fire at all. viessmann d6 error

or a Viessmann-trained technician. Professional intervention is necessary if: How to reset a Viessmann boiler Verify fan and air supply A: No

Sudden power cuts, brownouts, or a faulty earthing in your home’s electrical system can confuse the boiler’s electronics, triggering D6. viessmann d6 error

The exact meaning of the d6 code depends on the type of Viessmann unit you own: