Why is the car air conditioner cooling but with low air volume?
3 Answers
Reduced air volume in a car air conditioner is often caused by a clogged air filter. Below is an introduction to car air conditioning systems: 1. Air Conditioning Layout: Different types of air conditioning systems have varying layout methods. Currently, integrated heating and cooling air conditioning systems are widely used in passenger cars. Their layout involves assembling components such as the evaporator, heater core, centrifugal blower, and control mechanisms together, collectively referred to as the air conditioning unit assembly. 2. Air Conditioning Components: Modern air conditioning systems consist of a refrigeration system, heating system, ventilation and air purification devices, and a control system. A car air conditioner generally includes components such as the compressor, electronically controlled clutch, condenser, evaporator, expansion valve, receiver-drier, piping, condenser fan, vacuum solenoid valve, idle speed controller, and control system. Car air conditioning systems are divided into high-pressure and low-pressure lines. The high-pressure side includes the compressor output side, high-pressure lines, condenser, receiver-drier, and liquid lines; the low-pressure side includes the evaporator, accumulator, return lines, compressor input side, and compressor oil sump.
I encountered this issue before while driving. The A/C was clearly blowing cold air, but the airflow was as weak as a mosquito's buzz. It was so bad that I had to stick to the car window on hot days, which was really annoying. After checking, I found that the cabin air filter was severely clogged with dust and leaves, blocking the airflow—just like a household fan obstructed by debris. It needed immediate cleaning or replacement. Another possible cause could be a worn-out blower motor spinning too slowly. Last time, I disassembled it myself for inspection, and after replacing the filter, the airflow returned to normal. I recommend cleaning the filter during routine maintenance instead of waiting until the airflow weakens. This way, you won’t end up sweating buckets while driving in summer.
Encountering a situation where the air conditioning cooling effect is acceptable but the airflow is weak can be quite frustrating. Start with the simplest solution: if the cabin air filter is clogged with too much dust and debris, the airflow will be restricted and become weaker. This component can get dirty every couple hundred kilometers and should be replaced regularly. Another possibility is a faulty fan, where the motor is aging or the resistor is damaged, preventing the fan from reaching higher speeds. When inspecting, listen to the fan's sound—if it's humming but there's no airflow, it's likely a filter issue. Sometimes, poor contact in the control panel switches can also affect the airflow settings. These issues may seem minor but have significant impacts. If left unaddressed, the cooling performance will deteriorate, so it's best to handle them early.
