Innovation Water Heaters
– Edge [i] Controller
Venting and Combustion Air Design Guide
TAG-0090_A
•
GF-5056
•
2/20/2020
Technical Support
•
(800) 526-0288
•
Mon-Fri, 8 am - 5 pm EST Page 7 of 39
1.6.
PRESSURE RANGE
•
For individually vented units, the exhaust system must be designed so that pressure
measured at every point is in the range from
-
0.10” W.C. to +0.81” W.C.
(-25 Pa to 202
Pa)
.
•
For common vented units, the exhaust system must be designed so that pressure
measured at every point is in the
range of
-
0.10” W.C. to +0.25” W.C. (-25 Pa to 62 Pa)
.
•
Pressures below
-
0.10” W.C. (-25 Pa)
(more negative) may cause flame instability.
•
Pressures above
+0.25” W.C. (62 Pa)
for common vented units, or
+0.81 W.C. (202 Pa)
for individually vented units (more positive), will prevent flue gases from exiting.
1.7.
EXHAUST FANS
If the Innovation-Edge
water heater’s exhaust system incorporates an exhaust fan, the system
designer must size the vent pipe diameters, select the fan and determine the location of the fan
sensor to maintain a -0.1
” to +0.25” W.C. (-25 Pa to 62 Pa) pressure range at the outlet of each
unit. Also, the designer must ensure that the exhaust fan material is acceptable for use with
Category IV appliances.
1.8.
EXHAUST MUFFLER GUIDELINES
Innovation-Edge units require an exhaust muffler when they are installed in a noise-sensitive
application and
when the exhaust vent ducting is relatively short in length. The following criteria
should be used to determine when to include a field-installed muffler in an Innovation-Edge
installation:
•
The total linear length from exhaust to termination is less than 25 linear feet (7.5 linear m)
in length and the vent terminates in close proximity to residences, offices, hotel/hospital
rooms, classrooms etc.
For
manifolded exhaust
systems, the total vertical section includes only the common vertical;
individual unit vertical connectors are not included in the determination.
EXAMPLE: If the installation has a 20 foot (6.1 m) common vertical, and each unit has a
10-foot vertical connector, the total vertical section is only 20 feet (6.1 m). Because this
length is less than 25 linear feet (7.5 m), a muffler is required.
If the muffler must be mounted horizontally, add a condensate drain and trap with the drain port
oriented downward.
Contact your local AERCO sales representative for more information on the AERCO
exhaust muffler.
1.9.
Elbow Quantity and Separation
The quantity and angle of elbows and the distances between them can influence
the system’s
exhaust and combustion air pressures, as well as its acoustical behavior. Designers should
consider minimizing the quantity of elbows in the design and the use of angles less than 90°,
whenever possible. Five or fewer elbows are recommended for individual venting/connections;
five or fewer are recommended for common sections.
The minimum distance required between
two elbows is 5 feet (1.52 m)
.
