Lennox Hearth Gas Stove - Manual (Page 13)

1
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
f
lue
r
estriCtors
This stove requires a balanced flue to ensure proper com-
bustion. As such, flue restrictors may need to be installed
depending on the vent configuration of your stove. The
drawings on the following page show all the allowable
pipe configurations for the Vision™ gas stove. To properly
install the flue restrictor, find your pipe configuration in the
drawings on the following page and note which restrictor
setting is recommended. The flue restrictor is shipped in
the firebox of your stove. To install the restrictor, see Figure
18. Remove the two 5/32” allen head screws (A below).
Using pliers, repeatedly bend the unwanted portion of the
flue restrictor and discard. Install the flue restrictor using
the two 5/32” allen head screws according to the diagram
below. Install the flue restrictor screws in their original holes
in the top of the firebox. Restrictor positions are based on
tests run in a laboratory.
Storm Collar
Vertical Termination
Cap
Ceiling Firestop
Framing 10”x 10”
Roof - Maintain 1”
Clearance to
Combustibles
Pipe
Length
Flashing
Hand break to remove
unwanted restrictor
Light Obstructor
(only used for Vision25 w/short
horizontal run & no flue restrictor)
Position 1 Flue Restrictor Position 3 Position 2
A
v
ertiCal
v
ent
i
nstallation
Important Notes
1. All vertically terminated vent installations use 6-5/8”x 4”
Security™ Secure Vent™ pipe*.
2. If the vent passes through a ceiling or floor, a firestop
- Simpson #963 or Security #SV4BF - is required.
3. If the vent passes through the roof, a roof flashing -
Simpson #943 or 943S or Security #SV4FA or SV4FB
- and storm collar - Simpson #953 or Security #SV4FC
- are required.
4. A 1-inch clearance from the vent pipe to combustible
materials must be maintained.
5. A maximum of either two 45º elbows or two 90º elbows
may be used. See page 14 for allowable offsets.
6. The maximum system height is 30 feet and the minimum
is 10 feet.
14” Snorkel
min 12”
Figure 17
Figure 1
Figure 18