A conditioning system (2) for electrical equipment (E) of a vehicle (1), comprising a heat exchanger (3) inside of which a conditioning fluid of a conditioning circuit (4), configured to exchange heat with the electrical equipment (E), circulates, and heating means (10) configured to directly heat at least one of the walls (7', 7") of the heat exchanger (3). The system has been developed in particular for the circuit for maintaining the temperature of the high-voltage battery and its heating when the outside temperature is low.