Abstract: A regulating valve for a heat-transferring medium has a valve member controllable primarily by an electrical actuating member, but in the event of failure of the electrical actuating member, a thermostatic actuating member, operating independently of the electrical actuating member and of electric power, is provided in order to prevent damage to the system by driving the valve member when a predetermined temperature is exceeded.

Abstract: A cooling system for an internal combustion engine with at least two cylinder rows, in particular for a V-engine for a motor vehicle, has a coolant radiator and a thermostat valve for controlling a flow of coolant from coolant outlets of the cylinder rows, through or bypassing the coolant radiator, and back to the coolant inlets of the cylinder rows. The coolant outlet of one of the cylinder rows is directly connected with an inlet of the coolant radiator, and the coolant outlet of another cylinder row is directly connected with a bypass inlet of the thermostat valve. A bi-directional intermediate line is arranged between the bypass inlet of the thermostat valve and the inlet of the coolant radiator.