The auxiliary kettle is an important part of the automobile cooling system, usually called the expansion tank, which plays the role of balancing the pressure of the tank.
When the engine temperature is high, the liquid expands, then a part of the antifreeze flows into the auxiliary kettle through the tank lid; When the temperature drops and the cooling system pressure is negative, the system inhales the antifreeze of the auxiliary kettle into the cooling system through the tank cover.
