For Telecom shelters, enclosures and rooms.


Free Cooling is cost-effective controlled ventilation: the Telecom shelter or enclosure is cooled by means of ambient air without a compressor. Dantherm’s Free Air Cooling unit, the Flexibox, provides total heat management and significant energy savings on cooling in Telecom sites hosting GSM, UMTS or LTE networks.

Flexible, quality-minded cooling solutions

Dantherm offers multiple Flexibox solutions of different capacities, input voltage options and controller versions. The 6th generation features the Dantherm CC3000 controller with included dual-zone cooling, night mode and browser-based remote control.

Combine with existing solutions to save energy

The Flexibox as the sole cooling solution is adequate for cooling Telecom base stations in most climate conditions. In warm climates and in climates with high temperature peaks, a combination of free cooling and an air conditioner is a good choice. The combination prolongs the service life of your existing air conditioner and generates significant energy savings, when the free cooling is active.

Free cooling with extended air path protection

All of the Dantherm Free Cooling products operate with a slight overpressure. This ensures that only fine-filtered air enters the enclosed environment. For extreme weather conditions, Dantherm offers extended air path protection: the Dantherm AirMaze (pat.pend.). The AirMaze discharges sand, rain, snow and leaves before they reach the filter for maximum protection.


  • Radio base stations
  • Telecom shelters
  • Electronics enclosures
  • Power supply rooms
  • Network & computer rooms
  • Drive stations
  • Automation control cabinets
  • Hybrid Telecom Sites
  • DC Powered Sites

Features and Benefits

Dantherm Flexibox Free Cooling 810 and 900

  • Extremely energy-efficient: savings in all types of climates
  • Total heat management: control of multiple external units
  • Stable operation: stepless fan speed control
  • Clean internal environment: overpressure system
  • Extended air path protection: Dantherm AirMaze
  • Flexible installation: both indoor and outdoor
  • Low maintenance costs: washable compact filter
  • Maximum security: remote monitoring and configuration
Voltage AC or DC DC DC AC
Voltage 48 48 230
Max capacity in kW
at Δt = 10°C
7.8 8.1 8.6
Max air flow m³/h 2,333 2,450 2,590
Weight in kg 25.5 25 25
Cooling modes – Dantherm Flexibox 810 900
Automated change of cooling mode bullet bullet
Free Cooling bullet bullet
Emergency cooling in case of overheating bullet bullet
Emergency cooling in case of AC mains failure bullet bullet
Night mode bullet
Installation – Dantherm Flexibox 810 900
Outdoor installation bullet bullet
Indoor installation bullet bullet
Door installation  bullet bullet
Power supply – Dantherm Flexibox 810 900
230V AC – 50/60 Hz bullet
48V DC bullet bullet
Controller type – Dantherm Flexibox 810 900
Dantherm CC3000 controller for 48 V DC and 230 V DC bullet
Dantherm CC4 controller for 48 V DC bullet
Controller features – Dantherm Flexibox 810 900
WebGUI online management system bullet
Dual-zone cooling (optional) (bullet)  bullet
SD card reader for settings change and data logging bullet bullet
Display on controller    bullet
Optional external controller display bullet
RS 485 cable connection for laptop or remote monitoring bullet

 Dantherm AirMaze



Indoor-mounted Free Cooling units bullet
Outdoor mounted Free Cooling units bullet
Protection against wind-driven water, sand, snow and leaves bullet bullet