STULZ CyberMod Retrofit Fan Box

EC Fan Retrofit Kits for reduced OPEX

Easy-to-install, variable speed EC Fan Retrofit kits replace belt drive DWDI blowers for a clean, efficient upgrade to legacy data center air handlers.

Extend the Life, Efficiency and Reliability of these Existing Systems

  • Liebert systems

  • Data Aire systems

  • Compu-Aire systems

  • Airflow systems

  • ATS systems


  • No changes required to the primary electric or piping

  • Provides superior air distribution

  • Built-in fan redundancy

  • Easy installation

  • Quiet operation (low vibration, no inverter whine)

  • Low maintenance (no belts to adjust, no belt dust, no greasing)

  • Made in the USA


The STULZ CyberMod EC Fan Retrofit Kit has distinct energy saving advantages over other similar retrofit kits on the market, which use variable frequency drive (VFD) motors.

EC Fans are more efficient at partial load, where many data centers are running because they maintain efficiency throughout the entire speed and load range. They do not rely on incoming line voltage, which results in a more precise air flow.  Lower motor temperatures result in a higher net cooling capacity, possibly reducing the number of air conditioners required. 

*Savings estimate is derived from actual performance test results of (1) Liebert model FH740C with 10 hp forward curved centrifugal fan vs. (1) Liebert model FH740C modified with the STULZ EC Fan retrofit kit, against 0.3” of external static pressure. Results may vary.



  • Extend the life, improve efficiency & reliability of existing systems

  • 2 and 3 fan configurations available

  • No changes required to the primary electric or piping


  • Welded aluminum construction

  • Provides superior air distribution

  • Built-in-fan redundancy

  • Easy installation

Noise & Maintenance

  • Quiet operation - low vibration, no inverter whine

  • Low maintenance - no belts to adjust, no belt dust, no greasing


  • Energy saving advantages: 20% by replacing the fans only, at full flow

  • Up to 60% when allowing additional control options, partial load operation

  • EC Fans operate at lower speeds, lower energy, even airflow

  • Fast ROI - typically within 2 - 4 years and qualifies for utility rebates

  • EC Fans consume less energy, therefore higher net cooling capacity

  • EC Fans provide optimized under-floor pressure and balanced airflow


Control and monitoring

  • STULZ E2 controller ties directly to or replaces existing controller
  • Fan speed control is independent of CW valve control operation
  • Update existing control options (under-floor pressure control, return or supply air temperature control, independent fan and valve control)
  • Communicates with BMS - optional

Learn More


Contact us

Sales for All Products Areas in United States

  • STULZ Air Technology Systems, Inc.

    STULZ Air Technology Systems, Inc.

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