The structure of the warm air water tank is actually a miniature version of the radiator of the engine water tank, and there are many small cooling pipes in it, which are as easy to block as the radiator of the water tank. After the inside of the warm air water tank is blocked, the coolant flows slowly, the flow rate becomes smaller, and the heat is insufficient, so the air conditioner warm air is naturally not hot.
2. The cooling system lacks coolant.
Coolant, commonly known as antifreeze, comes from this, and its principle is different from that of household air conditioning heating. Automobile warm air circulation is to connect a pipeline in parallel in the small circulation pipeline of engine coolant, which is connected with a warm air water tank, and the blower blows the warm air water tank to generate warm air, which is how the air conditioning warm air comes from. The lack of coolant in the cooling system is the most common and easily solved fault phenomenon that causes the warm air not to be hot.
You can see the location of the heater tank from the inside of the engine compartment. In some models, the position of the warm air water tank will be higher than that of the cylinder block and cylinder head, or even higher than that of the cylinder head, thus ensuring that the coolant will circulate in the cylinder block and cylinder head first in case of insufficient coolant. After the coolant is replenished, the warm air tank will be filled with boiling coolant, and the warm air will naturally heat up.