![background image](http://html1.mh-extra.com/html/empire-comfort-systems/mantis-bf28-b/mantis-bf28-b_installation-instructions-manual_2404125011.webp)
30259-6-0314
Page 11
VENTING REQUIREMENTS
WARNING
This fireplace must not be vented with any other appliances,
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 fireplace
into a fireplace chimney or building chase.
WARNING
Upon completion of the installation, carefully inspect the en-
tire 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 re
-
quires special venting materials and installation procedures. In
-
stallations can be Conventional (1-pipe) and Direct Vent (2-pipe).
Venting must be completed with 1-1/2 inch diameter pipe. In se
-
lecting a location for installation, it is necessary to provide ade
-
quate 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 with (3) 90° elbows. 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 fireplace or
away from the fireplace.
Note:
If the vent run dips or sags, condensation may become
trapped and cause the unit to not operate properly.
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 Figures 2 and 3.
Single flue (one-pipe) installations must have a minimum clear
-
ance of 2 inches on the back of the fireplace for combustion air.
Note: If vent length requirements are not followed, the unit
will not operate properly.
Figure 3 - Colinear Direct Vent
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’
Figure 2 - Single Flue