Method for exchanging coolant in a cooling system, a control unit, a cooling system and an electric vehicle or vessel comprising the cooling system

A method for exchanging coolant in a cooling system, which cooling system comprises at least one pump, an inlet conduit, an outlet conduit, a plurality of sub-part cooling systems, and wherein the inlet conduit is connected to at least one external coolant source and each sub-part cooling system is independently fluidly couplable to the inlet conduit and the outlet conduit via at least one pump or at least one valve, the method comprises:

• controlling said at least one pump to flow coolant in the cooling system from the at least one coolant source via the inlet conduit, through the cooling system, to the outlet conduit until the coolant in the cooling system has been at least partly exchanged;
• controlling the at least one pump or the at least one valve to open fluid communication to and from one sub-part cooling system at a time in a sequence;
• in each part of the sequence, controlling the at least one pump or the at least one valve to close fluid communication to and from any other sub-part cooling system;
• and
• in each part of the sequence, controlling the at least one pump to flow coolant from the at least one coolant source, through the respective sub-part cooling system, to the outlet conduit so that coolant in the respective sub-part cooling system is at least partly exchanged.