Greenheck DG / DGX with Pilot Ignition (463555 IOM) (Pre-2008) - Manual (Page 27)

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Step 6 Adjust the Water Bleed-Off Rate
The water bleed-off rate is dependent on the water’s mineral content. The bleed-off should be adjusted based
on media’s mineral deposits after two weeks of service. See the picture below for location of bleed-off valve.
Step 8 Put the Unit into Service
Remove the jumper, and energize the blower(s). Verify proper operation.
Start-Up - Evaporative Cooling Recirculating (Optional)
Step 1 Check the Installation
The media may have been removed during installation, so its
orientation should be double checked. The media should be
installed with the steeper flute angle sloping down toward the
entering air side. See the figure on the right.
Verify that the stainless steel caps and distribution headers
are in place. The headers should be located over the media
towards the entering air side. The caps should be placed over
the headers.
Leaving Air Entering Air
45°
15°
Step 2 Check the Pump Filter
Check that the pump filter is around the pump inlet. See the picture below.
Step 3 Fill the Sump and Adjust the Float
Turn on the water supply and allow the pan to fill. Adjust the float valve to shut-off the water supply when the
sump is filled to within 1 in. of the bottom of the overflow. See the picture below.
Step 5 Check the Flow Rate
The pumps should provide enough water to saturate the media in 45 to 60 seconds. Consult the factory, if
adequate flow is not achieved.
Bleed-Off
Valve
Overflow
Pump
Filter
Threaded Float
Adjustment
Supply
Connection
Float
Valve
Step 7 Set the Optional Auto Drain and Fill
Set the auto drain and fill timer and temperature settings. Timer settings are t1: 1.0, 10min and t2: 0.4, 60h
Temperature is typically set to 45ºF. See the pictures below.
IMPORTANT!
Check the media for minerals after two weeks of service and adjust the bleed-off rate accordingly.
NOTE!
A jumper will need to be installed in the control
center to power the evaporative pumps with the
blower(s) off. Reference the unit’s ladder
diagram to determine proper terminals.
Evaporative
Timer
t2 settings
t1 settings
Evaporative Freeze
Protection
Temperature
Setting
Step 4 Break-in the Media
Open the bleed-off valve completely and saturate the
media with the blower(s) off for no less than 20
minutes. Start-Up
Medial Orientation
Evaporative Cooler Set-Up