* Refrigerant Handling: The refrigerant used in car AC systems (R-134a in most likely in your vehicle, but check your system) is under high pressure and requires specialized equipment to handle safely. Improper handling can result in serious injury, including burns from escaping refrigerant and exposure to toxic fumes. Refrigerant also damages the ozone layer and needs to be handled by professionals who follow proper recovery and recycling procedures.
* System Diagnostics: Before recharging, you need to diagnose *why* the AC isn't working. Is it low on refrigerant due to a leak? Is the compressor failing? Is there a problem with the condenser, evaporator, or expansion valve? Simply adding refrigerant to a system with a leak is wasteful and ineffective, and could even damage the compressor. Professional equipment is needed to identify leaks and other issues.
* Vacuuming: Before adding refrigerant, the system needs to be thoroughly vacuumed to remove air and moisture. This is crucial to prevent damage to the compressor and other components. You need a vacuum pump capable of achieving a high vacuum to do this correctly.
* Specialized Tools: You need specialized tools and gauges to measure refrigerant pressure and temperature accurately, as well as to add the refrigerant in the correct amount. Adding too much or too little can damage the system.
In short, while it *might* seem like a simple task, recharging an AC system is complex and potentially dangerous. The cost of a professional recharge is far less than the potential cost of a damaged compressor or other system component, or even a personal injury. Take your van to a qualified mechanic or AC specialist for proper diagnosis and repair.
