The principle of truck warm air heating is that the engine will generate heat when it works. At this time, the warm air is turned on, and the blower in the car will blow the hot air generated by the engine into the car, which will raise the temperature inside the car.
Therefore, if the water level of the truck warm air tank is too high, the water in the tank may not circulate normally, thus affecting the heating effect of the warm air. But it is not directly related to the heat of warm air itself.