according to ol' rip off diesel giant it's very necessary to change that unit when working on your ac system. ( the thing, even though there's oil going through it all the time, can rust internally??) I wonder why, and most of all, what does that thing do???
I'm certainly no specialist here, in europe we have a rather mild climate so nobody cares that their MB's AC-system is complete junk
input greatly appreciated.
also, I wonder, why not just drain the accumulator when working on the ac. I mean, there's moisture in it, so get it out and re-use it, right?