Why does the car leak coolant when the air conditioner is turned on?
3 Answers
It should be condensation water. The following is a related introduction to car air conditioning: 1. Air conditioning layout: Different types of air conditioning systems have different layout methods. Currently, cars widely use integrated heating and cooling air conditioning systems. The layout involves assembling components such as the evaporator, heater radiator, centrifugal blower, and control mechanism together, known 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. Car air conditioning generally includes components such as the compressor, electronically controlled clutch, condenser, evaporator, expansion valve, receiver-drier, pipelines, condenser fan, vacuum solenoid valve, idle speed controller, and control system. Car air conditioning is divided into high-pressure and low-pressure pipelines. The high-pressure side includes the compressor output side, high-pressure pipelines, condenser, receiver-drier, and liquid pipelines; the low-pressure side includes the evaporator, accumulator, return pipelines, compressor input side, and compressor oil sump.
I often hear friends complain about coolant leaks when the car's air conditioning is turned on, especially in summer. When the AC is running, the engine speed increases, causing a surge in cooling system pressure. If the seals are aged or have small cracks, they're prone to leakage under high pressure. Hoses, water pumps, or connectors in the cooling system may deform from long-term use—they seem fine normally but reveal issues when pressurized by the AC. If left unrepaired, coolant loss can lead to engine overheating or even a blown head gasket, making repairs much more complicated. I once drove an old car with the same issue, and inspection revealed a worn-out radiator connector gasket. I recommend going to a repair shop ASAP to locate the leak point—a pressure test can pinpoint it. Don't skimp on maintenance costs; proactively replacing aging components prevents bigger problems.
Last month, my car experienced coolant leakage when the air conditioning was turned on. Running the AC increases engine load and raises the pressure in the cooling system. If there are leaks in hose connections or the radiator cap, coolant can gush out under high pressure. Running out of coolant can cause the engine to burn out, so safety comes first. It's best to first check if the pipe seals are faulty or if there are any leakage points near the condenser. I fixed the issue by replacing a hose—it wasn't a difficult repair. Regularly maintaining the cooling system is important, and if you notice any leaks, stop using the AC immediately and have a professional mechanic take a look.
