Dacor ERV36-ER, Installation Instructions Manual

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7
Installation Specifications
Duct Work Design Tips
Wherever possible, reduce the number of transitions •
and turns to as few sharp angles as possible. Two
staggered 45° angles are better than one 90°. Keep
turns as far away from the hood exhaust as possible,
with as much space between each bend as possible.
For best performance, use round duct instead of rect-
•
angular, especially when elbows are required.
If multiple elbows are used, try to keep a minimum of
•
24” of straight duct between them. Avoid “S” or “back to
back” configurations of adjacent elbows.
In regions where the weather gets extremely cold,
•
thermal breaks, such as a short section of non-metallic
duct, should be used to avoid indoor heat loss. The
break should be located as close to the pass through
point to the outside as possible.
Do not use flexible metal duct.
•
Calculating the Maximum Duct Run Length
Do not use duct work that is smaller in cross-sectional •
area than the required duct sizes in the table to the
right.
For best performance, keep the duct run as short
•
as possible and never exceed the maximums stated
below.
The maximum straight duct length for the raised vent
•
system depends on the model of remote blower used
with vent system and the number of elbows and tran-
sitions used. The equivalent number of feet for each
elbow and transition must be subtracted from the maxi-
mum straight length to compensate for wind resistance
3 1/4" x 10"
90° Elbow
3 1/4" x 10"
45° Elbow
3 1/4" x 10"
90° Flat Elbow
Transistion
3 1/4" to 8” Round
45° Elbow
Round Duct
90° Transistion
3 1/4" x 10" to
8" Round
90° Elbow
Round Duct
15 Feet 7 Feet
20 Feet
4 Feet 4 Feet
8" Diameter - 3 Feet
10" Diameter - 2 Feet
25 Feet
8" Diameter - 7 Feet
10" Diameter - 5 Feet
Transistion
3 1/4" to 10" Round
Equivalent Lengths - Duct Elbows and Transitions
To determine the maximum allowable length of the duct
work, subtract all of the equivalent lengths of the elbows
and transitions listed below from appropriate Maximum
Equivalent Straight Lengths.
For example, for a raised vent system using 10 inch
duct, a REMP3 remote blower and three (3) 90° elbows:
From the Maximum Equivalent Straight Lengths table, •
the maximum length without transitions and elbows is
40 feet.
The total equivalent length of the three (3) 90
• ° 10 inch
elbows is
3 X 5 feet = 15 feet.
The maximum amount of straight duct that can be used
•
with a REMP3 and the elbows is: 40 feet - 6 feet = 34
feet.
Duct Size
Used
Maximum Equivalent Straight Lengths of
Duct Work
Using Model
REMP3 Remote
Blower
Using Model
REMP16 Remote
Blower
8 Inch 50 feet (15.2 meters) 60 feet (18.3 meters)
10 Inch 40 feet (12.2 meters) 70 feet (21.3 meters)
3 ¼” X 10” 40 feet (12.2 meters) 60 feet (18.3 meters)