Question

What is the difference between adsorption and condensation dehumidifiers?


Answer

Basically, there are two different types of dehumidifiers.


The most common is the condensation dehumidifier. By "dehumidifier" we usually mean so-called condensation dryers. This means that the water removal works by means of the condensation principle.

The condensation dryer cools down inside so that the humid room air condenses on the cooling coil, the water is then collected in the water tank. Condensation dryers have a compressor and a closed refrigerant circuit. The warmer the air in the room, the more they can dehumidify. So it must not be too cool to ensure efficient operation. Manufacturers say that they already dehumidify from 

5 °C, which is true. However, at cold ambient temperatures the performance is low. To keep the operation efficient, temperatures of at least 10-15 °C should prevail in the room. If above that, all the better.


Then there are the so-called adsorption dryers.

In adsorption dryers, the moisture is attracted by the so-called sorption wheel with a structure (similar to honeycombs) and removed by means of compressed air (small fan) and heat (heating element) into the water tank or via the water hose. However, because of the integrated heating element, adsorption dryers draw more electricity than condensation dehumidifiers. In addition, they emit warm air. This is around 10-12 °C warmer than the air drawn in. Depending on the situation, the room may warm up a little. The adsorption dehumidifiers have the special property that the dehumidification performance is not dependent on the room temperature. The dehumidification performance is constant from 1 °C room temperature. Therefore, adsorption dehumidifiers are ideal at ambient temperatures of 1-10 °C, because condensation dehumidifiers can no longer work efficiently there.