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27297-5-0511
Page 11
VENTING REQUIREMENTS
WARNING
This appliance must not be vented with any other appli-
ances, even if that appliance is of the condensing type.
Common venting can result in severe corrosion of other
appliances or their venting and can allow combustion
gases to escape through such appliances or vents. Do not
vent the heater into a fireplace chimney or building chase.
WARNING
Upon completion of the installation, carefully inspect the
entire flue system to assure it is properly sealed. DO NOT use
any vent material other than what is specified in this manual.
Leaks in the flue system can result in serious personal injury
or death due to exposure of flue products, including carbon
monoxide.
The Mantis is classified as a “Category IV” appliance, which
requires special venting materials and installation procedures.
Installations can be Conventional (1-pipe) and Direct Vent
(2-pipe). Venting must be completed with 1-1/2 inch diameter pipe.
In selecting a location for installation, it is necessary to provide
adequate clearances for servicing and proper installation.
All vent and combustion air pipes and fittings must be Schedule
40 PVC and meet the ANSI/ASTM Standard D1785. Cement must
conform to ASTM Standard D2564.
Maximum Vent Length is 40 feet. The minimum vent length
is 12 inches.
Each 90° elbow used in the vent system will be
the equivalent to 3 feet, and each 45° elbow is equivalent to
1.5 feet, which should be added to the overall vent length.
See
Table 1.
It is recommended that the Mantis Power-Vent High-Efficiency
Fireplace be located on an exterior wall for ease of venting. The
flue exhaust pipe and inlet air pipe should be located between wall
studs. The required opening for venting is 1-7/8 inch in diameter
for 1-1/2 inch PVC pipe.
The minimum distance from the center of the vent cap to the near-
est outside corner or obstruction is 12 inches. The flue outlet must
be at least 12 inches from any opening which flue gases could en
-
ter the building. See Figure 1. The flue outlet must be a minimum
distance of 6 feet from any pressure regulator.
The bottom of the exhaust vent terminal and the air intake shall
be located at least 12 inches above grade and must be vented
outside. It is recommended the exhaust and intake be located 12
inches from the maximum snow level.
The flue pipe must be supported on horizontal vent runs. The flue
pipe needs to be supported every 3 feet. All horizontal runs of the
flue must be pitched ¼ inch per foot either towards the heater or
away from the heater. The minimum vent length protruding from
outside the wall is 6 inches. For two-pipe installation, a minimum
distance of 3 inches and maximum distance of 24 inches must be
maintained between the pipes. See Figure 2.
Single flue (one-pipe) installations must have a minimum clear
-
ance of 2 inches on the back of the heater for combustion air.
Vent Freezing Protection
When the vent pipe is exposed to temperatures below freezing
(i.e. when it passes through unheated spaces, chimneys, etc.)
the pipe must be insulated with 1/2 inch thick sponge rubber
insulation, Armaflex-type insulation or equivalent. Insulating pipe
is important to avoid condensate icing.
For proper operation, the flue exhaust must extend 6 inches from
the outside wall before applying an elbow.
Note: If vent length requirements are not followed, the unit
will not operate properly.
12” MIN
TO GRADE.
(RECOMMENDED
12” MIN
TO MAX
EXPECTE
D SNO
W LEVEL
)
TYPICAL
BOTH
PIPES
6” Min
3” Min
24” Max
Figure 2
Table 1 - Equivalent Vent Length Example
EVL = Equivalent Vent Length
EVL must be greater than or equal to 1’
and
less than or equal to 40’
EVL
=
90º elbow + 4’ straight pipe + 45º elbow
+ 2’ straight pipe + 45º elbow
+ 3’ straight pipe
=
15’
EVL
=
3’
(90º elbow)
+
4’
(straight pipe)
+
1.5’
(45º elbow)
+
2’
(straight pipe)
+
1.5’
(45º elbow)
+
3’
(straight pipe)
=
15’