In Line A/C Freon Filter
 

Has anyone installed an In-line freon filter in their A/C systems? I see where many of the other manufacturers are using them in their systems and several internet A/C parts houses are selling them. Are they necessary? Do they work? Where would one installed in our 1980's model A/C systems?

Seems to me that should your A/C refrigerant gets contaminated to the point that you have need of filtering something serious is in the process of failing anyway.

thats really what the reciever/dryer is.