The present disclosure relates to heat and temperature control. The teachings thereof may be embodied in temperature-control units for electronic components. For example, a temperature-control unit may include: a housing defining a receptacle for the component and a channel system for a fluid. The channel system runs from an inlet via a nozzle and via a cavity to an outlet. The housing comprises a wall structure with an inner surface forming an impact surface situated opposite a nozzle mouth and an outer surface serving as part of the receptacle.