Norcold SCQT-6406 Refrigerant Charging

Oct 19, 2013
58
Hunter 37C 3 Centerport
SV Shadow came with a Norcold SCQT-6406 refrigeration unit for the icebox.
I don't know if this was standard equipment on the 85's, but I'm grateful to have it.
My problem of course is I don't have a clue how to recharge it.
To start, the original refrigerant was R-12. R-12 is no longer made and has been replaced with R-134A.
I bought a can of R-134A and a delivery hose and attached it to the suction valve on the copper piping, but It didn't seem to work.
I opened the valve for 5 seconds, turned it off and waited 5 minutes to see if the icebox's cold plate got cold. It did not.
I repeated this procedure a number of times but no change. In fact, the can of refrigerant seemed pretty full when I finally gave up.

My current thinking is that I have to purge the system of it's existing refrigerant before I can charge it, but I really don't know.
Attached are photos of the unit and it's valves.

Any advise will be appreciated. TIA
 

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Oct 19, 2013
58
Hunter 37C 3 Centerport
Since no one's replied here, I've come to the conclusion that this was an aftermarket item.
I've posted this request for help on the "Ask All Sailors" forum and got a lot of good advice.
Thanks anyway.