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Liebert® DSE™ Free-Cooling System

Breakthrough technology with proven reliability, high efficiency, easy scalability and low maintenance.

How It Works

The Liebert DSE is the first pumped refrigerant economization system for data centers, providing free cooling throughout much of the year. Four system components work together to maximize free cooling and ensure higher protection by providing fail-save economization with full direct expansion (DX) backup.

These components are all managed by the unit’s Liebert iCOM control system, which adjusts for partial to full economization, based on the IT load and the return air temperatures to use 100% of potential economizer hours annually.

Warm Temperature

The unit’s variable-speed evaporator fans, condenser fans and digital scroll compressors automatically adjust to match IT load and optimize energy usage. The unit can engage backup DX for additional capacity if needed.

Cooler Temperature

During cold temperatures, both refrigerant pumps are engaged, bypassing the unit's compressors to provide 100% free- cooling, allowing the system to operate at far greater efficiency than if one or both compressors were activated.

Cold Temperature

During cooler temperatures seasonally or overnight, the refrigerant pump is engaged, bypassing one of the unit's compressors, to provide partial free cooling, offsetting some of the compressor power usage.

Proof of Performance

The Liebert DSE provides considerable power savings over both legacy and new data center cooling technologies.

  • In a recent data center application in Pittsburgh, where the Liebert DSE replaced legacy direct expansion (DX) systems, electricity usage decreased by over 30 percent.
  • In its four-year history of data center installations, the Liebert DSE has saved more than 2.2 BILLION gallons of water, when compared to using chilled water systems.

In San Francisco, the Liebert DSE would provide full free cooling 65% of the year and partial free cooling 25% of the year, and direct expansion (DX) for only 10% of the year.

Why It's Unique

  1. Higher Efficiency and Reliability

    First and only pumped refrigerant economization system for data centers, much more efficient and reliable than traditional technologies.

  2. Less Maintenance

    No water treatment required, no dampers and louvers to maintain, automatic economizer switchover, eirect-drive EC fans with no belts or pulleys to maintain and lower refrigerant charge than traditional DX systems.

  3. Prevents Contamination

    No outside air is allowed into the data center.

  4. Provides More Annual Economization Hours

    Uses advanced controls that manage operations according to outdoor ambient temperatures and IT to maximize economization.

  5. Cuts Water Consumption and Expense

    Uses no water and therefore eliminates a need for costly water maintenance.

  6. Certified Performance

    California Title 24 compliant, making it available to California data centers as a prescribed economization option by the California Energy Commission, and AHRI Certified® for efficiency and capacity by the Air-Conditioning, Heating and Refrigeration Institute.

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