1, the structure of the warm air water tank is actually a miniature version of the engine water tank radiator, which has many small cooling pipes, which are as easy to block as the water tank radiator. 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 cooling liquid, which is also commonly known as antifreeze. Car air conditioning warm air 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, and the pipeline is connected with a warm air tank, and the blower blows the warm air tank to generate warm air, which is how the air conditioning warm air comes from;
3. Lack of coolant in the cooling system is the most common and easily solved fault phenomenon that leads to warm air not being hot. Causes and solutions of automobile warm air not being hot. The common fault of the thermostat is that it can't be opened, but the reason why the warm air is not hot due to the thermostat fault is that the thermostat can't be closed, commonly known as the thermostat is always open;
4. After the thermostat is opened normally, the coolant will circulate from the idle speed of the engine. If the water temperature is low for a long time in winter in the north, the air conditioning warm air will naturally not be hot. It is obvious from the thermometer that the pointer is obviously lower than the normal scale. In addition, long-term low water temperature of the engine will lead to high fuel consumption and increased wear (the engine is not working at the optimal temperature), so it is necessary to carry out maintenance and inspection immediately when the water temperature is low for a long time.