Abstract: Thermostat valves are disclosed for guiding the flow of coolant in an internal combustion engine, which includes three channels with a central valve chamber, the first channel including a first valve seat, and in which the thermostat valve includes a valve housing mounted within the valve chamber and including an opening facing the second channel and including a second valve seat, a tubular valve body movably mounted with respect to the valve housing along a valve axis between a first end position in which the tubular valve body bears against the first valve seat such that the first and second channels are in fluid communication and the first and third channels are blocked, and a second end position in which the tubular valve body bears against the second valve seat such that the first and second channels are in fluid communication and the first and third channels are blocked, and a temperature sensitive switch for moving the tubular valve body between the first and second end positions, in which the valve ho