Vaillant ecoTEC plus VU 446/5-5 (H-GB) Installation And Maintenance Instructions Manual page 16

Adequately secured
air/flue gas pipe
You can use a plume management kit to enable the termination point to be positioned and directed away from the building
fabric.
16
Balcony/eaves
Gutter
The flue pipe must
protrude beyond any overhang
Installation and maintenance instructions ecoTEC plus 0020261389_03