Greenheck Fan 473501 manual Ductwork Connections, Rail Mounting / Layout, Exhaust Weatherhood

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

tion

a

t

duct installation will result

R

o

in low airflow and

other

system effects.

POOR

tion

Length of Straight Duct

a

t

R

o

GOOD

Recommended Discharge Duct Size and Length

Unit Size

Blower

Duct Size

Straight Duct

Size

Length

ERCH-HP 20

9

14 x 14

36

ERCH-HP 45

10

20 x 20

36

ERCH-HP 55

12

20 x 20

36

ERCH-HP 90

15

28 x 28

60

All dimensions shown 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.

Rail Mounting / Layout

•Rails designed to handle the weight of the unit 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 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.

AirOutdoorHoodIntake

Supply/Exhaust

Opening

			B		A
Side view of unit on rails						Isometric view of unit
		Rail Mounting
	Unit Size			A			B
	ERCH-HP 20			5.0		41.0
	ERCH-HP 45			7.0		41.9
	ERCH-HP 55			5.5		53.0
	ERCH-HP 90			6.0		59.0

All dimensions are in inches.

Exhaust Weatherhood

The exhaust weatherhood is shipped separately as a kit with its own instructions.

Model ERCH-HP Energy Recovery Unit 11