85-03-01058-O
FV33i Gen 3
Page
37
3.2.18
Venting
The FV-44i Insert must be vented vertically to the outside and must use one of the approved co-linear
flexible ducting systems or a coaxial flexible ducting system. Mendota recommends that both exhaust and air
intake flex liners be run all the way to the vent cap. Seals between flex liners and unit top and vent cap must
be permanent and as airtight as possible.
Do Not Use any silicone sealants at flex pipe joints. Stove
gasket cements may be used at pipe joints but is not required
. Do use both securing screws and hose
clamps at all four flex connection points.
Maximum and Minimum Vent Lengths
Minimum vent run length required is 10’. Maximum vent run
allowed is 55’. Only vertical termination is allowed. No
horizontal runs are allowed with the vent system. Horizontal
offsets of less than 4’ are approved if the offset is angled at least
30-degrees vertically.
Run Liners to Vent Cap
When existing wood burning chimney size allows, run both the
4” exhaust liner and 3” air intake liner to the vertical vent cap. If
existing wood burning chimney size is too small to run both 4”
and 3” liners, consider converting to a coaxial flex system using a
4” exhaust flex and 6” air intake flex with spring spacers
between the two flex pipes.
Air Intake Liner Stubbing
When existing wood burning chimney, size is too small to run
both 4” and 3” liners, it is an option to cut the air intake flexible
duct short and run only the 4” vent flexible duct to the vent cap
connector. This is generally called “stubbing”. However,
understand that doing so may lead to venting problems when
weather storms approach. Variations between the air pressure
inside the home and atmospheric air pressures outside the
home can cause venting problems and performance failures.
Avoid “stubbing” if chimney flue size allows installation of both
liners fully to the vent cap.
MENDOTA RECOMMENDED VENT
COMPONENTS AND VENT KITS LIST
MENDOTA RECOMMENDED VENT COMPONENTS AND VENT KITS LIST
NOTE: Mendota “highly” recommends that you use one of the two vent caps listed below. Mendota has thoroughly
investigated, designed, and confirmed by testing that these two caps perform flawlessly during high wind speeds up to 40
MPH. Comparable tests on vent caps other than those listed below did not yield comparable results.
AA-11-04104
MENDOTA INSERTS SQUARE HOMESTYLE VENT CAP WITH BUILT-IN FLASHING, 4" X 3"
AA-11-04105
MENDOTA INSERTS ROUND VENT CAP WITH BUILT-IN FLASHING, 4" X 3"
AA-11-04106
MENDOTA INSERTS FLEX KIT (INCLUDES 3”x35’, 4”X35’, 4 Hose Clamps)
Basic Vent System
Screws
