refill has the problem of gas in the cylinder hindering the flow of propane going in. I have read some people use plier to pull the safety
valve out so you get more liquid propane inside. Otherwise some will freeze the bottle first.
These valves do leak and for my torch, I just leave the bottle attached all the time.
Just a FYI, I found out some info if propane or hydrocarbon is used for refrigeration
, only 40% of a r22 or r134a charge is used and if it does leak, up to 50% of the HC stays dissolved in the compressor oil
. Typically an upright fridge will have less than 2 ounces of a HC refrigerant needed and a HC refrigerant is a lot more energy efficient.