"Bill Noble" fired this volley in
:

So, why does your experience differ? could it be a drier
climate, or could it be something else? Note, I am not questioning
your advice/report, it makes perfect sense, I'm wondering why I can
get away with not doing all that stuff?


This particular vehicle had - at one time - a leak on the low pressure
side of the compressor. It had been run like that, recharged, run,
recharged over and over without fixing the leak.

So it was sucking in non-condensables more or less continuously every
time it ran out of refrigerant. In Florida, those consist of both air
and prodigious quantities of humidity. The long pull-down was partly due
to sucking the moisture out of the filter-drier (which can be re-dried
with a long-enough pumpdown).

LLoyd