Greenheck Fan HRE-55, HRE-20, HRE-90, HRE-45 manual Evaporative Cooling Modules, Evap Module Start-Up

Evaporative Cooling Modules

It is important to mount the heat recovery unit level to ensure proper operation and water drainage. Piping should be of adequate size to provide sufficient supply of water to meet the maximum demand of the evaporative coolers.

Evap Module Start-Up

1.After the energy recovery unit is set in place, run the overflow and drain lines to the exterior fittings on the evaporative cooler (drain & overflow connections at unit are 3⁄4-inch female pipe thread). The supply line can be attached at the downstream side of the evaporative cooler. A manual shut off valve should be mounted in the supply line near the unit for servicing purposes. Also, a trap should be installed in the drain line to prevent sewer gas from being drawn into the unit (see Figure 8).

2.The cooler will be prewired by the factory.

3.Check to make sure that the pump filter is around the pump inlet.

4.Turn the water on and allow the pan to fill up with water. The float should be adjusted to provide 2 inches of water depth in the sump.

5.Saturate the media without any airflow through the unit. A jumper wire is required on the terminal strip to provide power to the evaporative cooler pump (see the wiring diagram for the proper location). This saturation process will break-in the media and minimize the odors associated with the media. The media’s break-in period should be no less than 20 minutes. When the process is complete, remove the jumper wires in the control center.

Note: Evaporative media may foam for a short period following the initial start-up. Leave the bleed-off valve fully open until the foaming stops.

Indirect Evaporative Cooler

(Exhaust/Scavenger Airstream)

Direct Evaporative Cooler

(Outdoor/Supply Airstream)

6. After the media break-in period, the water flow rate over the media needs to be checked. The pumps should provide enough water to saturate the media in 1-3 minutes. If adequate flow rate is not achieved, consult with the factory.

7. The water bleed-off rate will now need to be adjusted. This measurement is 3 to 6 percent of

the media flow rate. The recommended flow rate is
11⁄2 to 2 GPM per
square foot of	Unit Size	Media Pad Top Area
media pad top area	HRE-20	1.5 ft2
(see table at right).	HRE-45	2 ft2
After the unit has	HRE-55	2.5 ft2
been installed and	HRE-90	3.3 ft2
running for two

weeks the unit should be checked for mineral deposits. If there are deposits, the bleed-off rate needs to be increased. Some areas of the country have water with greater amounts of dissolved minerals requiring a higher bleed-off rate.

Side of HRE Unit

Drain Line

Overflow

Evaporative

Cooling

Media

8. Verify that both airflow and system static pressure are in agreement with the specifications. If these conditions are met, check for water carry over from the discharge side of the media. If carry over is observed, check the distribution header for

holes or tears and the water standoff tube for blockage.

Trap

Manual

Shutoff

Drain Valve

Line

Sump

Roof Curb

Roof Line

9. After all final

adjustments are made,

remove the jumper

wires and replace all

access panels. The

unit is now ready for

FIGURE 8

Manual Shutoff Valve Supply Line

operation.

7