Abstract: Apparatus for adjusting a central heating installation, particularly in respect of the heat delivery of the appertaining radiator or radiators separately, for which purpose the or each radiator is provided with a presettable valve in the supply pipe for the heating medium, such as water. The apparatus is further provided with a temperature transducer on the supply pipe and a temperature transducer on the return pipe for the heating medium, and a control unit is provided which has at least three inputs, to two of which said temperature transducers of the supply and return pipes are connected, while to the third said input a room temperature transducer is connected.