How does the water in the water tank of the car heater circulate?

Cycle principle of automobile warm air water tank: 1. When the engine is working, it will generate a lot of heat. In order to dissipate heat, the engine drives the water pump to work through the belt, so that the engine coolant circulates and cools down; 2. When the temperature rises to a certain extent and the cooling liquid in the engine is not enough to cool down, the thermostat opens and the water tank participates in the circulation. The water pump injects the coolant in the water tank into the engine, cools it and returns it to the water tank (radiator) for cooling, and then circulates it; 3. For heating in the car, a tee is added in the coolant circulation channel, so that the coolant absorbed by the engine temperature flows through the warm air mechanism, then cooled by the warm air fan, and then the heat is transferred to the car. So warm air is actually the same principle as adding a fan to the engine water tank, except that one is blown into the car and the other is blown out.