How does evaporative cooling work? | Celsius

Creating a better and greener working environment

How does evaporative cooling work ?

air evaporative cooling systems

Evaporative cooling is a very simple method of cooling air without using refrigerants. A direct air evaporative cooler, using wetted filter pads, cools air by bringing it into contact with water. Water evaporates into the air stream and cools it. The amount of cooling is dependent upon the temperature and relative humidity of the air.

In the UK the maximum theoretical air off temperature is 22°C. In practice the actual temperatures achieved when evaporative cooling data centres in UK conditions can approach 24°C on the very warmest days. This allows full compliance with ASHRAE temperature standards.

In an evap cooling unit water is brought into the cooler from the mains water supply and is pumped up to the top of the unit using a circulation pump. The water is then dispersed over the Celdek pads using a water distribution system which allows the water to flow continually over the pads. The pads become saturated, air is drawn through the pads and the water evaporates causing the air to cool.

The cool air is then ducted round the building to provide cooling by means of an energy efficient axial fan

When cooling data centres the performance of a Celsius EcoCooler is dependent upon the temperature of the air and its relative humidity. Higher temperatures give greater cooling. Low relative humidity gives greater cooling.

Why should you choose us for your evaporative cooling? Find out here.

Celsius Evaporative Cooling Systems  evaporative air cooling


Supply Air Temperature Achieved

Amb. Relative Humidity
Temp 20% 30% 40% 50% 60% 70% 80%
20°C 12.0 13.0 14.5 15.5 16.5 17.5 18.5
25°C 16.0 17.0 18.5 20.0 21.0 22.0 23.0
30°C 19.5 21.0 22.5 24.0 25.0 26.5 28.0
35°C 23.0 25.0 26.5 28.5 30.0 31.5 32.5

When using evaporative air cooling in the UK during a typical hot period the ambient temperature approaches 30°C. This coincides with a Relative Humidity of under 50%. As the air passes over the pads it will typically cool down to about 22°C. There is less cooling in the night as the temperatures reduce and the humidity rises.

Evaporative Cooling data centres is extremely energy efficient due to the simple nature of the process when compared to using conventional air conditions.

For more information and for a no obligation quote, please call us on 01926 887470.

Our Latest Jobs

Aberystwyth Council

Three years ago Celsius installed an EcoCooling Data centre cooling system for Aberystwyth Council at their Aberaron data centre, it worked that well delivering all the savings promised (over 80 tonnes of carbon per annum) as part of their carbon reduction program, therefore, when the cooling system in their main Data centre in their state of the art head office required a new back up system they approached us for our innovative solution.

Read more

Go Outdoors

Celsius have recently installed evaporative cooling systems for 6 Go Outdoors stores that suffered from severe summer overheating problems, the first was at Taunton and as this was so successful the Oxford store soon followed. The Celsius EcoCooling evaporative cooling approach has now been established as the Go Outdoor’s chosen solution for all of their stores, it fits in perfectly with their low carbon approach.

Read more