What Causes the Lack of Heat in the Heater While Driving?

[AndresRose]

Reasons for the lack of heat in the heater while driving: 1. The thermostat is stuck open or opens too early, causing the cooling system to enter the major circulation prematurely. When the external temperature is very low, especially when the vehicle is moving, the cold air quickly cools the antifreeze, preventing the engine coolant temperature from rising and resulting in insufficient heat from the heater; 2. The water pump impeller is damaged or slipping, reducing the flow rate through the heater core, which leads to inadequate heat transfer; 3. There is an airlock in the engine cooling system, which disrupts proper coolant circulation, causing high coolant temperature but insufficient heat from the heater. The car air conditioning system is designed to regulate and control the temperature, humidity, air cleanliness, and airflow within the vehicle cabin to maintain a comfortable environment.