I want to decommsion an old HP and haul it to the landfill where they will recover the refrigerant. (like they do with old refrigerators)
In the archives I came across Turtle's "self suck" method of running the HP in A/C mode, close the liquid valve and then close the suction valve once it's "slurped" all it's refrigerant and packed it back into the condensor.
At what point do I shut the suction valve? When pressure completely drops to 0 or when the compressor sounds like it's getting pissed off?
Even though the unit is old (1979 vintage) I really don't want to damage it. As an option, I might choose to try and sell it on CL since it's still operational.
I see there are lots of wanted ads for old HP's but I assume is to salvage the copper content.