compresser oil

Never. It is a completely hermetic sealed system and you cannot access it to change it or check it.

oil

The comp is and open type comp where u have acess to change the oil the filiter dryer was changed as far as basic rule if there is no problems is there a rule for changing the oil or should it be left alone

is it in a refrigeration system and what kind

As above, is this an A/C or refrigeration system. Acid level can be checked without draining or changing oil.

so bascially if u check the acid level in the system to make sure it is not high and change your filiter dryer u should be ok? what iam trying to ask is that (poe or min) oil is not the same as changeing oil in a car where as it breaks down and after time u have to change it as long as your level is good your system is dry u should be ok? Iam dealing with an ref 404a and also an a c system r 22

oil

Thank u for your help everyone has a diff answer for as changeing oil in a comp Ialways felt as long as the system was dry the acid levels were not high, your oil level was correct and u werent dealing with a burnout u were ok just wanted to get some input on that,as far as dealing with ref or a c r 22 404a or 134a poe or mineral does that mater in your opion? Thank u

An refrigerant containing system is a closed system. No air or other contaminants get in it from normal use. So it doesn't need changed like a engine's oil does.