Absorption system is the first and the oldest cooling technology in the world. Having the cooling cycle, it is necessary to have two elements which absorbs both elements and needed to have a noble gas to pressurise.This pressured mixture would be ignited by a heating source therefore it provides the phase change and eventually provides the cooling.
As the heating source;
- 12/24-110/120-220/240 V
In the small systems like fridges, minibars and etc. generally ammoniac and water are in use as an element. As a noble gas, helium and hydrogen are the usable gas groups.