What Causes a Car's Air Conditioner to Not Blow Warm Air?
1 Answers
Issues with a car's air conditioning heating system not producing warm air can be categorized into two main causes: problems with the engine cooling system or malfunctions in the heating control mechanism. Potential cooling system problems include: 1. A thermostat that is constantly open or opens too early, causing the cooling system to enter a large circulation prematurely. When the external temperature is very low, especially when the car is moving, cold air quickly cools the antifreeze, preventing the engine water temperature from rising and consequently the heater from warming up. 2. Damage or slippage of the water pump impeller, leading to insufficient flow through the heater core, which prevents heat from rising. 3. Air pockets in the engine cooling system, which disrupt the circulation, causing high water temperature and resulting in the heater not producing warm air. If there are persistent air pockets in the cooling system, it may indicate a damaged cylinder head gasket allowing air into the cooling system. If the inlet pipe of the heater core is very hot while the outlet pipe is relatively cool, this suggests a blockage in the heater core, which should be replaced. Issues with the air control mechanism: 1. The car's heater uses a blower to direct heat from the heater core into the cabin. If the airflow is insufficient or the distribution of hot and cold air is poor, the heat from the heater core cannot dissipate effectively, leading to inadequate heating. In this case, first check if the air filter is dirty or clogged, clean it, and replace it if necessary. 2. Inspect the operation of the blower at all speed settings to ensure each setting achieves sufficient airflow. If the knob is adjusted to the heating position, the airflow is strong, and the direction is normal, but cold air is still blowing out, check if the control cable for the heater box's hot/cold air flap is detached, if the heater impeller is damaged, or if the flap is dislodged. Resolving these issues should restore the heater's functionality.
