Emerson Liebert Economizer Solutions User Manual

The Liebert Air Economizer is an option for Liebert DS downflow units, Liebert CW chilled water 

downflow and Liebert Challenger 3000 downflow units. The Liebert Air Economizer uses cool outdoor 

air in mild climates to condition indoor spaces. It is functional only on cooling units with Liebert 

iCOM

®

 controls that have been factory-wired and configured to accommodate the Liebert Air 

Economizer.
The Liebert Air Economizer is supplied with electrical wiring for connection to the cooling unit, 

outdoor air sensors, return air sensors and a temperature-and-humidity-sensing unit.
Special firmware is loaded into the primary cooling unit at the factory to permit the primary cooling 

unit to control the Liebert Air Economizer.

Installation and operation requires outside-air entry ductwork with louvers, screening and filtration 

to prevent intrusion of precipitation, particulates, vermin and unauthorized entry (see Figure 1).
Proper installation also requires a customer-provided powered relief-air discharge to rid the structure 

of the outside air drawn in for cooling. The relief-air discharge must be equivalent to the airflow of the 

total of all cooling systems equipped with the Liebert Air Economizer.
A flange is provided to attach the Liebert Air Economizer to the outdoor air duct Figures 2, 3 and 4.