Dantherm climate soloutions logo headers

Free air cooling technology

7 min read
Dantherm telecoms cooling web

Free cooling equals cost-effective controlled ventilation for telecom site because of their ability to cool by means of ambient air without a compressor. Dantherm free cooling solutions operate with an overpressure, delivering filtered air into the room, thereby ensuring a clean environment, for example for radio transmission equipment. Energy savings can be huge – with our Flexibox units we can document energy and operating cost savings of up to 90% at Telecom sites that are hosting networks like GSM, UMTS or LTE.

The impressive reduction in energy consumption stems is most often a result of comparing the free air cooling unit technology to Telecom sites that have previously applied traditional air-conditioners. By using free cooling, the overall thermal management running expenditure is simply slashed by this impressive percentage.

How does free cooling work?

Free cooling solutions create a fine-filtered overpressure. Motorised dampers are recommended to ensure optimum air flow in the shelter and to prevent ambient air from entering the shelter or room.

Total heat management

The free cooling solutions provide the option of total heat management in the telecom shelter, as the system controls both connected heating and air conditioning systems. Even surveillance and alarms are part of the free cooling solution.

6th generation of free cooling technology

The free cooling technology has been used by Dantherm for more than a decade and has been through 6 design generations resulting in vastly improved and optimised solutions that stand on years of accumulated knowhow.


When choosing a cooling technology that utilizes ambient air to cool, it is important to understand the concept of delta t (Δt):

Δt = t internal - t ambient

The capacity is stated as e.g. 288 W/K. This means that by a difference in temperature of 1Kelvin = 1°C, the cooling capacity is 0.288kW.

Example: Average ambient temperature: 20°C, desired internal temperature: 25°C = Δt = 5 (25-20).


Humidity in relation to free cooling is a frequently asked question. When using free cooling, you may apply humid and cold ambient air into an electronic enclosure to cool it down. When the humid ambient air meets the warm air in the enclosure, it is heated and the relative humidity will decrease – leaving no risk for condensation on the electronic equipment.

Installing a free cooling unit like Dantherm’s Flexibox at an existing site will:

  • Lower maintenance costs for the complete cooling system as the unit will be relieving the existing air-conditioner from some of its hard and expensive work
  • Extend air-conditioner lifetime because of the above
  • Less emergency trips to sites due to air-conditioner breakdowns
  • Limit site breakdowns as it will also act as emergency cooling in case of air-conditioner breakdown or power outage, thereby securing a longer “up-time” in case of overheating
  • Give technicians longer reaction time to arrive at site before site breakdown

For help choosing the right system for your project, don’t hesitate to get in touch with our team.

Related products

Dantherm Flexibox 810-900 – free cooling unit
Dantherm climate soloutions tab flip

Free cooling

Free cooling is cost-effective controlled ventilation – the telecom shelter or enclosure is cooled by means of ambient air without a compressor.

Dantherm DC 450 – dc air conditioning unit
Dantherm climate soloutions tab flip

DC air conditioning unit

Dantherm’s DC air-conditioners are slimline true DC air-conditioners for energy-efficient cooling in telecom networks.

Dantherm DFC 350-450 – displacement free cooling unit
Dantherm climate soloutions tab flip

Displacement free cooling

The Dantherm DFC 350 and 450 are slim passive cooling units utilising the displacement free air cooling technology.

Dantherm TKS 60 – high capacity free cooling unit
Dantherm climate soloutions tab flip

High-capacity free cooling

TKS 60 is high-capacity free air cooling designed to control the internal environment of communication shelters using a minimum of energy.

Dantherm DC 3500 – dc split air conditioning unit
Dantherm climate soloutions tab flip

DC split air-conditioning

The Dantherm DC Split air-conditioner is a high-efficiency, purely DC-powered split air conditioner for Telecom networks

Dantherm AirMaze II – air vent weather protection
Dantherm climate soloutions tab flip

Air vent weather protection

AirMaze is a compact air path protection capable of removing wind-driven water and sand particles from even high air speed applications.

Featured insights

Insights Content telecom cooling
Dantherm climate soloutions tab

Why free cooling keeps electronic devices cool for less than traditional air conditioning systems

Photo of Tobias Netz
Tobias Netz 8 min read
Dantherm electronic cabinet web
Dantherm climate soloutions tab

Monoblock and split air-conditioning solutions for telecoms

Photo of Tobias Netz
Tobias Netz 4 min read
Dantherm building
Dantherm climate soloutions tab

A quick comparison between the two technologies

Photo of Tobias Netz
Tobias Netz 5 min read

Reach out to an expert

Need help with choosing the right solution? Our team of over 100 climate control experts can assist.
You can also reach out or join the discussion on our Social Media. Check out our LinkedIn page.