The height of a system chimney should be appropriate in order to be fully effective. We measure it from the level of the emissions T-pipe to the outlet above the roof.
- for gas furnaces – min. 4 m,
- for oil furnaces – min 5 m.
This level is also affected by the roof angle as well as the distance of a chimney from the crest.
It is important for a chimney outlet to be situated at least 60 cm above the crest, irrespective of the roof angle and construction.