Why does a car's air conditioner have a lot of water flow but not cool properly?
2 Answers
Here are the reasons why a car's air conditioner may have excessive water flow but fail to cool effectively: 1. Excessive refrigerant: Many car owners often assume that the air conditioner isn't cooling due to a lack of refrigerant, which is a common misconception. In such cases, it is advisable to consult a professional technician for an accurate diagnosis. Blindly adding refrigerant can lead to an overcharge in the air conditioning system, increasing the pressure in the pipelines and reducing heat dissipation, ultimately worsening the cooling issue. 2. Insufficient refrigerant: The primary cause of low refrigerant levels is usually minor leaks in the system. If there isn't enough refrigerant in the air conditioning system, the amount sprayed into the evaporator via the expansion valve will also decrease. As a result, the heat absorbed during the refrigerant's evaporation phase diminishes, leading to reduced cooling capacity. 3. Excessive impurities in the refrigerant or lubricating oil, causing minor blockages: If there are too many contaminants in the refrigerant or lubricating oil within the air conditioning system, the filter screen may become clogged. This restricts the flow of refrigerant, increases resistance, and reduces the amount of refrigerant passing through the expansion valve, resulting in insufficient cooling performance.
The other day I was tinkering with an old Corolla in the garage. The owner complained that the AC was draining a lot of water but not cooling at all. This is a common issue I encounter, mainly caused by refrigerant leakage leading to poor heat dissipation. The water flow is actually condensation discharged by the evaporator during AC operation—excessive water isn’t a problem and even indicates the blower is working, but the lack of cold air is concerning. The most likely reasons are low refrigerant levels or a small leak in the system. If the compressor lacks sufficient pressure, it can’t effectively cool the air. I usually advise owners to first check the dashboard temperature indicator or simply test the compressor oil pressure. If the oil pressure is unstable, refrigerant needs to be topped up; otherwise, a faulty compressor can be expensive to repair. Additionally, a dirty filter can block the vents and hinder airflow—cleaning it yourself can save money. I’ve seen many cars return to normal after just replacing the filter. Driving with a weak AC can cause drowsiness, so don’t delay repairs for too long.
