procedure of welding split air conditioner leakage in steps
Accurate diagnosis of a refrigeration system leak
First, see the lost cooling capacity to diagnose just why the system is not working.
If you know that the refrigerant level is low or zero, don't just re-charge the system. Find and fix the refrigerant leak.
If the refrigerant gas leak is in a valve or access port, such as the service ports to which the HAVC technician connects her gauge set, the valves there may be able to be cleaned and salvaged, or the valves may need to be replaced.
If the refrigerant gas leak is in the air conditioning or heat pump copper tubing a repair should be easy - the damaged line is re-soldered using high silver content solder and a high-temperature torch.
If the refrigerant gas leak is in the condensing coil or in the evaporator coil, repair might be possible, but we're less optimistic that repair is possible, but it might be, as we explain
Use a halogen gas leak detector to pinpoint refrigerant gas leaks and for thorough inspection & testing of the entire refrigerant piping system, including the condensing and evaporating coils.