Provided the volume and pressure of a gas remain the same, the maximal quantity of water that the gas can contain only depends on the temperature: the lower the temperature, the less grams of water vapour per m3 are in the gas mixture at 100% RH.
Based on this fact, the freon cooler fulfils an intermediate function in the inert gas drying process. By bringing down the temperature to a few degrees over the freezing point, the dewpoint of the gas is lowered to about + 5 °C.
