Warm wind is turned on in winter, and the water temperature is very low.

Does the subject want to ask "the reason why the heating temperature of automobile air conditioner drops in winter and the water temperature is normal"? Insufficient coolant, cooling fan failure, circulating water pump failure, thermostat failure.

1. Insufficient coolant: the engine cooling system lacks antifreeze, and the water temperature at the heat conducting side of the engine is too high, which affects the heating system.

2. Failure of cooling fan: The water temperature in the engine cooling system is too high, the cooling fan fails, and the cooling fan is damaged, which is controlled by the thermostat when working. Only when the water temperature reaches a certain temperature, the cooling fan starts, the water temperature drops rapidly, and the cooling fan stops working.

3. Failure of circulating water pump: The failure of the water pump in the engine cooling system can't make the water circulate, which leads to the rapid rise of water temperature. At this time, the warm air system will be turned off to prevent the engine from overheating.

4. Thermostat failure: The heater system has a thermostat, and the thermostat failure is always in the closed position, so that the engine cooling system is always in a low temperature state. When the car is running, the engine load will increase and the heat will also increase. However, due to the thermostat failure, the engine water temperature can not rise to the working temperature, resulting in abnormal operation of the heater system.