Corp. Air Conditioner User Manual
5
Model ERVe Energy Recovery Unit
1 Fan
Wheel
Dia.
1 Fan
Wheel
Dia.
R
o
t
a
t
i
o
n
R
o
t
a
t
i
o
n
R
o
t
a
t
i
o
n
R
o
t
a
t
i
o
n
Length of Straight Duct
GOOD
POOR
GOODPOOR
GOOD
POOR
Tu rning
Vanes
Tu rning
Vanes
SYSTEM EFFECT FACTOR CURVES
FPM X 100
OUTLET VELOCITY
0 5 10 15 20 25 30 35 40 45
1.2
1.0
0.8
0.6
0.4
0.2
0.0
STATIC PRESSURE LOSS
CURVE 1
CURVE 2
CURVE 3
CURVE 4
Roof Curb Mounting
Roof curb details including duct location dimensions,
are available on Roof Curb Assembly Instructions,
Part Number 472119.
Rooftop units require curbs to be mounted first. The
duct connections must be located so they will be
clear of structural members of the building.
1. Factory Supplied Roof Curbs: Roof curbs are
Model GKD. The GKD ships in a knockdown
kit (includes duct adapter) and requires field
assembly (by others). Assembly instructions are
included with the GKD curbs.
2. Install Curb: Locate curb over roof opening and
fasten in place. (Refer to Recommended Roof
Openings). Check that the diagonal dimensions
are within ±1/8 inch of each other and adjust
as necessary. For proper unit operation, it is
important that the installation be level. Shim as
required to level.
3. Install Ductwork: Installation of all ducts should
be done in accordance with SMACNA and AMCA
guidelines. Duct adapter provided to support
ducts prior to setting the unit.
4. Install Insulation: One-inch deep insulation
pans were provided with the curb assembly.
Install insulation prior to setting the unit.
Insulation is not included from the factory.
5. Set the Unit: Lift unit to a point directly above
the curb and duct openings. Guide unit while
lowering to align with duct openings. Roof curbs
fit inside the unit base. Make sure the unit is
properly seated on the curb and is level.
Unit Size L W LF WF
Curb Weight
(lbs.)
ERVe-20 61.125 40.375 64.875 44.125 93
ERVe-35 63.375 48.5 67.125 52.25 106
ERVe-45 67.375 55.5 71.125 59.25 120
ERVe-55 78.25 65.5 82 69.188 148
All dimensions are in inches. Weights are for 14-inch high
GKD type curbs.
L
W
LF
L
WF
W
LENGTH WIDTH L INCLUDING FLANGE W INCLUDING FLANGE WEIGHT
ERVE-20 61.125 40.375 64.875 44.125 93
ERVE-35 63.375 48.5 67.125 52.25 106
ERVE-45 67.375 55.5 71.125 59.25 120
ERVE-55 78.25 65.5 82 69.188 148
Curb Outside Dimensions and Weights
4.844
1.549
0.775
Insulation Pan
(Insulation not included)
Unit Base
Roof Curb
1.895
Unit Side
Curb Cap Details for Factory Supplied Roof Curbs
Curb Outside Dimensions - continued
Recommended Discharge Duct Size and Length
Model Blower Size Duct Size Straight Duct Length
ERVe-20 9 14 x 14 36
ERVe-35 10 20 x 20 36
ERVe-45 12 20 x 20 36
ERVe-55 15 28 x 28 60
All dimensions shown in inches.
• Recommendedductsizesarebasedonvelocitiesacrossthe
cfm range of each model at approximately 800 feet per minute
(FPM) at minimum airflow and up to 1600 fpm at maximum
airflow. Recommended duct sizes are only intended to be a
guide and may not satisfy the requirements of the project.
Refer to plans for appropriate job specific duct size and/or
velocity limitations.
• Straightductlengthswerecalculatedbasedon100%effective
duct length requirements as prescribed in AMCA Publication
201. Calculated values have been rounded up to nearest foot.
Ductwork Connections
Examples of poor and good fan-to-duct connections
are shown below. Airflow out of the fan
should be directed straight or curve
the same direction as
the fan wheel rotates.
Poor duct installation
will result in low airflow
and other system
effects.
1 Fan
Wheel
Dia.
1 Fan
Wheel
Dia.
R
o
t
a
t
i
o
n
R
o
t
a
t
i
o
n
R
o
t
a
t
i
o
n
R
o
t
a
t
i
o
n
Length of Straight Duct
GOOD
POOR
GOODPOOR
GOOD
POOR
Tu rning
Vanes
Tu rning
Vanes
SYSTEM EFFECT FACTOR CURVES
FPM X 100
OUTLET VELOCITY
0 5 10 15 20 25 30 35 40 45
1.2
1.0
0.8
0.6
0.4
0.2
0.0
STATIC PRESSURE LOSS
CURVE 1
CURVE 2
CURVE 3
CURVE 4