What are the symptoms of a leaking evaporator?
2 Answers
Evaporator leaks manifest as symptoms where the air conditioning fails to cool, and a smell of automotive air conditioning refrigerant or refrigerant oil can be detected in the cabin. Here is relevant information: 1. Refrigerant Composition: Consists of polyester-based synthetic oils (such as polyalkylene glycol). Since nitrile rubber is incompatible, polybutadiene rubber is used as the sealing element. Characteristics include being colorless, odorless, non-toxic, non-flammable, and non-explosive. Currently, R134a refrigerant is widely used. R134a does not damage the atmospheric ozone layer but still has a certain greenhouse effect and is currently one of the alternatives to R12. 2. Refrigerant Replacement: There is no fixed time cycle for adding or replacing refrigerant. Whether replacement or addition is needed depends mainly on the cooling state of the air conditioning. The simplest way to evaluate the cooling state is to measure the temperature at the air outlet, which is generally between 5 to 10 degrees Celsius, within the normal range, with slight variations among different vehicle models. After excluding reasons such as heat dissipation or refrigerant leakage, the refrigerant can be replaced. Additionally, after repairing or replacing components of the air conditioning system, the refrigerant is also replaced to ensure the cooling effect of the air conditioning.
Last summer while driving, I noticed the AC suddenly stopped blowing cold air. The air from the vents was lukewarm, not icy cold as before. The car interior became unbearably hot like a steamer, and the temperature wouldn't drop even after running the AC for a long time. Adjusting the temperature setting lower didn't help either. After parking, I detected a faint chemical odor resembling moldy wet cloth, and could vaguely hear a hissing sound from the front of the car, as if there was an air leak somewhere. Concerned about refrigerant issues, I took it to a repair shop. The mechanic diagnosed a minor freon leak in the evaporator causing insufficient pressure and reduced cooling capacity, with some oily residue observed at the leak point. They warned that delaying repairs could worsen the leak, potentially overloading and damaging the compressor, leading to much higher repair costs. My advice is to get it checked immediately when noticing reduced AC performance, before peak summer heat causes bigger problems.
