Ravelli HR EVO 300 SMART Manuel D'installation, D'utilisation Et D'entretien page 68

This type of installation (See Fig.4) requires an insulated chimney
pot, even if the entire smoke conduit is installed outside the
building.
In the lower part of the chimney there is a "T" type fitting installed
with inspection cap.
It is prohibited to install a 90° bend for the initial segment, since
the ashes would quickly obstruct smoke passage, causing draught
problems in the boiler. (See Fig.2)
This type of installation (See Fig.5) requires an insulated chimney
pot, since the entire smoke conduit is installed inside the building,
and the part is located inside a pre-existing chimney pot.
In the lower part of the boiler there is a "T" type fitting installed with
inspection cap just like for the chimney pot.
It is prohibited to install a 90° bend for the initial segment, since
the ashes would quickly obstruct smoke passage, causing draught
problems in the boiler. (See Fig.2)
This type of installation (See Fig.6) requires a horizontal section to
connect to a pre-existing chimney pot.
Respect the slope indicated in figure, in order to reduce the ashes
depositing in the horizontal tube. In the lower part of the chimney
pot, there is a "T" type fitting installed with inspection cap, in the
same was as the chimney pot opening.
It is prohibited to install a 90° bend for the initial segment, since
the ashes would quickly obstruct smoke passage, causing draught
problems in the boiler. (See Fig.2)
HR EVO 300-350 SMART
use and maintenance manual
External
air intake
Air-tight steel sheet metal
External air
intake
T fitting for condensation
Exter-
nal air
intake
Rev.0 18/12/2019
ENG
Pag.68
Protection from rain
Insulated chimney
T fitting with condensation
drain and
collection chamber
Fig.4
Protection from rain
Covering sheet
T fitting with collection
chamber for condensation
Fig.5
Protection from rain
Fig.6