Guys, NO AIR in AC SYSTEM!!!! it if not immediately but eventually kill your ac system. the problem is that different oils in ac systems can create acids and explosive vapors when mixed with moisture (it depend on type of oil in the system).
This is from EPA manual for 609 certification:
Leak Testing Although the EPA has not mandated leak repair at this time, when servicing an automotive air conditioning system, you should repair leaks whenever possible. Adding refrigerant to a leaking system is harmful to the environment, a waste of valuable refrigerant and it is unlawful in some states. Before beginning a service job, the technician should perform a thorough visual inspection and leak check of the system. 6 When using an electronic leak detector, always follow the manufacturer's operating instructions. In addition to the manufacturer's instructions, the following should be observed: 1. Always leak test with the engine off. 2. Only, a small amount of refrigerant is required to perform a leak test. A gauge reading of 50 psi is all that is needed. At temperatures below 50°F., leaks may not be measurable, since 50 psi may not be attainable. 3. To avoid contaminating the tip of your leak detector, remove excessive dirt from suspected leak areas. Do not use cleaners or solvents, your detector may be sensitive to their ingredients. 4. Visually inspect the system, and look for signs of air conditioning oil leakage, damage, and corrosion on all lines, hoses, and components. Each suspected area should be carefully checked. 5. Follow the system around in a continuous path to ensure that no areas are missed. If a leak is found, continue to check the remainder of the system for additional leaks. 6. At each area checked, move the probe tip around the location at about 1" per second while holding the probe no more than 1/4" above the surface of the area being leak checked. 7. To verify an apparent leak, blow shop air into the area of the suspected leak to clear any refrigerant that may linger and repeat the leak check. 8. To leak test an evaporator core, operate the air conditioner with the blower motor on high for a minimum of 20 seconds. Shut the air conditioner and blower motor off and wait for the refrigerant to accumulate. Insert the leak detector probe into the blower resistor block or the condensate drain hole (if no water is present). If the detector indicates a leak, the evaporator or the line connections to the evaporator are leaking. After a system has been opened for repair, the system should be properly leak tested before charging with refrigerant. The system should hold a deep vacuum (27 in HG. or more) for at least one minute before charging. If the system will not hold a deep vacuum, a minimum amount of refrigerant (enough to produce a positive pressure) can be added for leak testing. An alternate method of leak testing is to use Nitrogen (an inert gas) to pressurize the system, and then pinpoint leaks with a soap and water solution. Whenever dry nitrogen from a cylinder is used in a service procedure, you should always charge through a pressure regulator, and have a pressure relief valve installed downstream from the regulator. NEVER pressurize the system with oxygen or compressed air. When mixed with refrigerants and their lubricants, oxygen or compressed air can cause an explosion.
Mark
it happened so quick and i regret not vacuuming before adding air in the second time, i should of done that.. so sad but learned my lesson.
