Abstract: The present invention proposes adding an alkaline solution or a mixture of two or more alkaline solutions to the agent system of absorption machines operating with ammonia or methylamine as the agent and water as the solvent. This addition of an alkaline solution or an alkaline solution mixture has a number of advantageous effects. These are, i.a.1. The dissolving respectively expelling heat of the agent is reduced, raising the output figure.2. The agent vapor generated is very pure. A dephlegmator is obviated.3. The alkaline solution makes steel surfaces inert when sealed from air and in a high vaccum, thereby obviating corrosion inhibitors.4. The viscosity of the solvent is reduced, decreasing pump operation.