Abstract: A method for achieving a specific temperature behavior of adjusting elements, operating in dependence on temperature, of valves or thermostatic apparatus is disclosed, and also an adjusting element, operating in dependence on temperature, of valves or thermostatic apparatus. Such adjusting elements work in many cases by means of pressure from a pressure chamber, which is provided with a liquid-gas filling. This filling is in many cases toxic or environmentally harmful, in order to achieve satisfactorily the desired temperature behavior. In order to be able to use also non-toxic and environmentally harmless substances, the pressure chamber is filled with a zeotropic mixture of at least two substances. The ratio of component substances is set in dependence on the desired temperature behavior.