The Venting System; General Information; Chimney And Liner Information - HearthStone Green Mountain Insert 70 Owner's Manual

The Venting System

G I
ENERAL NFORMATION
The venting system, made up of the chimney and
the liner inside the chimney, acts as the engine that
drives your wood heating system. Even the best
insert will not function safely and efficiently as
intended if it is not connected to a suitable chimney
and liner system.
The heat in the flue gases that pass from the insert
into the chimney is not waste heat. This heat is
what the chimney uses to make the draft that draws
in combustion air, keeps smoke inside the insert
and safely vents exhaust to outside. The heat in the
flue gas can be seen as the fuel the chimney uses
to create draft.
B -O P
LOCK FF LATE
To reduce the possibility of a cold air back draft
from the masonry chimney into the room, the
installation of a sheet metal block-off plate (A) is
recommended. When fabricating the block-off plate,
cut the pipe hole slightly larger than the liner
diameter and pass the liner through the hole. Install
the block-off plate and secure it with masonry nails.
Seal the joints between the plate and the chimney
with high temperature silicone and use stove
cement to seal between the pipe and the plate.
In Canada, the CSA B365 Standard permits 'Roxul'
type wool to be stuffed around the liner as it passes
through the throat area as an alternative to a sheet
metal block-off plate. However, this method is less
efficient than using a plate.
Figure 11 – Block Off Plate 1
Hearthstone Quality Home Heating Products, Inc ®
Figure 12 – Block Off Plate 2
S C
UITABLE HIMNEYS
Your wood insert will provide optimum efficiency
and performance when connected to a 6-inch
diameter chimney liner. The connection to a
chimney having a diameter of at least 5 inches
(Canada only) is permitted, if it allows the proper
venting of combustion gases and that such
application is verified and authorized by a qualified
installer. Otherwise, the diameter of the flue should
be 6 inches. The reduction of liner diameter to less
than 6" should only be done if the total height of the
masonry chimney is greater than 20 feet.
L I
INER NSTALLATION
The use of a chimney liner (rigid or flexible) is
recommended to ensure the best performance. To
ensure an optimal draft, it is also strongly
recommend adding a minimum of 12" rigid liner
between the top of the masonry chimney and the
rain cap. In all cases, liners should be installed in
accordance with the liner manufacturer's
instructions, including instructions for extension
above the masonry.
Use chimney liners listed UL 1777, ULC S635 or
CAN/ ULC S640.
In order to connect the insert to the liner, refer to
the section LINER CONNECTION.
18
Green Mountain Insert 70 (Model 8450)