Stulz Retrofit & Replacement Solutions

stulz banner high quality workmanship and engineering excellence
Energy efficient solutions for legacy computer room air handlers. STULZ offers EC Fan Retrofit Kits, CRAH Replacement Systems, and a Controller Retrofit, all designed to make data center cooling more reliable and energy efficient.

  • EC Fan Retrofit
  • Replacement CRAH
  • E2 Controller Retrofit


Stulz CyberMod

EC Fan Retrofit Kit
EC Fan Retrofit Kits significantly reduce the operating costs in your data center. Easy-to-install, variable speed EC Fan Retrofit kits replace belt drive DWDI blowers for clean, efficient upgrade to legacy mission critical air handlers.

  • 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.

Stulz Replacement CRAH

Direct Drop-In Replacement
Increase cooling capacity and achieve significant energy savings without redesigning your data center. STULZ Replacement CRAHs are high capacity, direct drop-in, chilled water units with modern EC fans. They replace inefficient legacy units with belt-driven fans and provide instant energy savings and improved performance.

  • No modification to existing piping mains, primary electric, or floorstand
  • STULZ V-Coil arrangement
  • Energy saving advantages of up to 40%, simply by replacing the CRAH
  • Additional energy savings of 50% and beyond can be achieved using advanced controls
  • Increased air volume at maximum fan speed
  • EC Fans operate at lower speeds, lower energy, even airflow
  • EC Fans consume less energy, therefore higher net cooling capacity
  • EC Fans provide optimized under-floor pressure and balanced airflow
  • Fast ROI; qualifies for utility rebates
  • Provides advanced communication and control capabilities
  • Lowers maintenance costs
  • Made in the USA

Stulz E2 Microprocessor Controller

Smart Controls
Standard controls across all products. STULZ E2 is the standard microprocessor controller across all STULZ product platforms. E2 provides precision monitoring and control of your mission critical environment.

STULZ E2 Controller ties everything together

  • Designed specifically for precision control of mission critical environments
  • Multiple I/O capabilities for all major components to optimize control for energy savings
  • Supports universal BMS interface for remote monitoring (address readable) and remote control (address writable)
  • Capable of network controllers in a workgroup (pLAN) to work as one (no BMS required)
  • Pre-engineered controls for economizers and adiabatic cooling
STULZ E2 Controller communicates with BMS/BAS systems via the following protocols:

  • BACnet IP
  • BACnet over Ethernet
  • BACnet MS/TP
  • HTTP
  • SNMP V1, V2c
  • Modbus IP
  • Modbus RTU

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