Intergas
- Horizontal or Vertical no white showing. No boxing allowed.
- All components must be accessible
Worcester Bosch
- Horizontal or Vertical flues white is allowed show as long as joints are siliconed.
Vaillant
- Horizontally flue white exposed is ok. Â Vertical no white showing. Weather tight box with inspection hatch possibly ok.
Viessmann
- White part of flue ok to be exposed as UV resistant. 300mm away from wall for vertical terminal. On vertical no white showing. 1m extension on vertical flue.