Fault 06 or 07 - Insufficient air supply or vent blockage

What does 06 / 07 mean?

These faults indicate that the boiler is not receiving enough fresh air for combustion, possibly due to blockages in the vent system or strong wind conditions.

• Insufficient air supply to the boiler
• Ice blockage on the vent termination
• Excessive flue pipe length
• Severe local wind conditions
• Incorrect side wall terminal location
• Defective fuse on the electronic fan control box (for 44/60 only)
• Defective pressure transducer

Click steps to track your progress.

1. 1

   Check for ice or other blockages on the vent termination outside the building.

2. 2

   Verify the maximum allowed flue pipe length for your installation.

3. 3

   If applicable, check the location of the side wall terminal for compliance with venting requirements.

4. 4

   If symptoms persist (for 44/60 models only), check for a defective or blown fuse on the orange electronic fan control box.

5. 5

   If all external checks fail, contact Viessmann support as a defective pressure transducer might be the cause.