* O-rings: These small rubber seals are found throughout the AC system, on connections between components like the compressor, condenser, evaporator, and drier. They are prone to hardening and cracking with age, leading to leaks. This is arguably the *most* common cause of leaks.
* Condenser: Located in front of the radiator, the condenser is vulnerable to damage from road debris. Bent fins or even small punctures can cause refrigerant leaks. Corrosion can also weaken it over time.
* Evaporator: Located inside the dashboard, the evaporator is harder to access and inspect. Leaks here are often more difficult to diagnose and repair, potentially requiring dashboard disassembly.
* Compressor seals: Worn seals in the compressor itself can leak refrigerant. A failing compressor is a more serious problem, often requiring replacement.
* Hoses and lines: The rubber hoses and metal lines that connect the various components can develop leaks due to age, cracking, or damage from rubbing against other parts. Look for any signs of chafing, bulging, or discoloration.
* Expansion valve/Orfice tube: This component regulates refrigerant flow into the evaporator. Leaks here are less common but still possible.
* Receiver/dryer (accumulator): This component filters the refrigerant and often contains a desiccant to absorb moisture. Leaks can occur at its connections.
Important Note: Pinpointing the exact location of an AC leak requires specialized equipment like UV dye and a leak detector. Visually inspecting the system for obvious signs of leaks (oil stains, refrigerant frost) can be helpful, but it's often not sufficient to identify the source. It's best to have a qualified mechanic diagnose and repair any AC leak. Improperly handling refrigerants can be dangerous.
