Greenheck ERCH - Energy Recovery Unit with Packaged DX (468151) - Manual (Page 6)

6
Energy Recovery Unit with Packaged DX
1 Fan
Wheel
Dia.
1 Fan
Wheel
Dia.
Rotat
io
n
Rotat
io
n
R
ot
ation
R
ot
ation Length of Straight Duct
GOOD
POOR
GOOD POOR
GOOD POOR
Turning
Vanes
Turning
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
S
TA
TIC PRESSURE LOSS
CUR
VE
1
CUR
VE
2
CUR
VE
3
CUR
VE 4
1 Fan
Wheel
Dia.
1 Fan
Wheel
Dia.
Rota
tio
n
Rota
tio
n
R
ot
ation
R
ot
ation Length of Straight Duct
GOOD
POOR
GOOD POOR
GOOD POOR
Turning
Vanes
Turning
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
S
TA
TIC PRESSURE LOSS
CUR
VE
1
CUR
VE
2
CUR
VE
3
CUR
VE 4
DUCTWORK CONNECTIONS
Examples of good and poor 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 .
ROOF CURB
SIDE OF UNIT
BASE
1 INCH INSULATION
E
D
C
A
B
Rail Layout
• Rails designed to handle the weight of the ERCH should be
positioned as shown on the diagram (rails by others) .
• Make sure that rail positioning does not interfere with the supply
air discharge opening or the exhaust air intake opening on the
ERCH unit . (Avoid area dimensioned “B” below) .
• Rails should run the width of the unit and extend beyond the unit
a minimum of 12 inches on each side .
• Set unit on rails.
B A
SUPPLY/EXHAUST
OPENING
OUTDOOR AIR
INTAKE HOOD
B A
SUPPLY/EXHAUST
OPENING
OUTDOOR AIR
INTAKE HOOD
Isometric view of unit on rails
Side view of unit on rails
RAIL MOUNTING
Model
Rail
Mounting
A B
ERCH-20 5 .00 41 .00
ERCH-45 7 .00 41 .90
ERCH-55 5 .50 53 .00
ERCH-90 6 .00 59 .00
All dimensions shown are in inches .
Model
Curb Cap Dimensions
A B C D E
ERCH-20 2 .00 2 .00 1 .00 0 .88 0 .75
ERCH-45 2 .00 4 .25 2 .00 1 .31 0 .50
ERCH-55 2 .00 4 .25 2 .00 1 .31 0 .50
ERCH-90 2 .00 4 .25 2 .00 1 .31 0 .50
All dimensions shown are in inches .
Curb Cap Details for Factory Supplied Roof Curbs
ROOF CURB MOUNTING - CONTINUED
Recommended Discharge Duct Size and Length
Model Blower Size Duct Size Straight Duct Length
ERCH-20 9 14 x 14 36
ERCH-45 12 20 x 20 48
ERCH-55 15 28 x 28 60
ERCH-90 18 32 x 32 60
All dimensions shown are in inches .
• Recommended duct sizes are based on velocities across the 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 .
• Straight duct lengths were calculated based on 100% effective duct length requirements as prescribed in AMCA Publication 201.
Calculated values have been rounded up to nearest foot .