I recentley spotted a product that I understand measures and removes any air from the recovery tank and results in purer refrigerant.
I guess i am just wondering what people think to this, and whether it is neccessary because I had planned on re-using some gas , which I had recovered from a system that worked very well but just had a low charge. If I was to re-charge this r134a gas straight into an ac system without having this kind of tool atached to the recovery cylinder would I also be getting air into the system from the recovery process that has entered into the recovery bottle along with the refrigerant? How can it give me purer refrigerant becuase surely any air will be removed when I purge hoses prior to charging, leaving me with pure refrigerant anyway..