A refrigerant recovery unit, the refrigerant recovery unit comprising: a) a charging circuit (425, 425a) configured to charge a refrigerant into a refrigerant system (200, 200a), wherein the charging circuit (425, 425a) comprises first and second service hoses (124, 124a; 128, 128a) each having a hose fill valve (401, 401a; 402, 402a) at an end; b) a refrigerant container (212, 212a) storing the refrigerant in fluid communication with the charging circuit (425, 425a) and a system oil separator (262,262a) wherein a valve (404, 404a) is installed on the second service hose (128,128a) at the end connecting said second hose to the refrigerant container; c) a scale (215, 215a) adapted to measure a weight of the refrigerant container (212, 212a); d1) a recirculating circuit (400, 400a) comprising first and second recirculating hoses configured to recirculate refrigerant contained in the first and second service hoses (124, 124a; 128, 128a) from a connection (226, 226a; 230, 230a) at each of the hose fill valves (401, 401a; 402, 402a) to the system oil separator (262, 262a) which is adapted to remove vapor refrigerant from the refrigerant such that the refrigerant contained in the first and second service hoses (124, 124a; 128, 128a) is liquid refrigerant before the refrigerant is charged into the refrigerant system (200, 200a); d2) a recirculating valve (403,403a) disposed in the recirculating circuit (400, 400a) between the system oil separator (262, 262a) and a point where the first and second recirculating hoses join; and e) a controller (216, 216a) configured to open the valve (404, 404a), and activate a first time delay function of 1, 2, 3, 4, or 5 seconds, to allow the refrigerant from the refrigerant container (212, 212a) to fill the first and second service hoses (124, 124a; 128, 128a) up to the hose fill valves (401, 401a; 402, 402a) and the recirculating circuit (400, 400a) up to the recirculating valve (403, 403a); f) wherein the recirculating valve (403, 403a) is controlled by the controller to open and allow the refrigerant from the first and second recirculating hoses to recirculate refrigerant to the system oil separator (262, 262a); and g) wherein the controller (216, 216a) is further configured to, after the first time delay, keep the recirculating valve (403, 403a) open such that vapor refrigerant is removed from the first and second service hoses (124, 124a; 128, 128a) and replaced with recirculated condensed refrigerant. a) a charging circuit (425, 425a) configured to charge a refrigerant into a refrigerant system (200, 200a), wherein the charging circuit (425, 425a) comprises first and second service hoses (124, 124a; 128, 128a) each having a hose fill valve (401, 401a; 402, 402a) at an end; b) a refrigerant container (212, 212a) storing the refrigerant in fluid communication with the charging circuit (425, 425a) and a system oil separator (262,262a) wherein a valve (404, 404a) is installed on the second service hose (128,128a) at the end connecting said second hose to the refrigerant container; c) a scale (215, 215a) adapted to measure a weight of the refrigerant container (212, 212a); d1) a recirculating circuit (400, 400a) comprising first and second recirculating hoses configured to recirculate refrigerant contained in the first and second service hoses (124, 124a; 128, 128a) from a connection (226, 226a; 230, 230a) at each of the hose fill valves (401, 401a; 402, 402a) to the system oil separator (262, 262a) which is adapted to remove vapor refrigerant from the refrigerant such that the refrigerant contained in the first and second service hoses (124, 124a; 128, 128a) is liquid refrigerant before the refrigerant is charged into the refrigerant system (200, 200a); d2) a recirculating valve (403,403a) disposed in the recirculating circuit (400, 400a) between the system oil separator (262, 262a) and a point where the first and second recirculating hoses join; and e) a controller (216, 216a) configured to open the valve (404, 404a), and activate a first time delay function of 1, 2, 3, 4, or 5 seconds, to allow the refrigerant from the refrigerant container (212, 212a) to fill the first and second service hoses (124, 124a; 128, 128a) up to the hose fill valves (401, 401a; 402, 402a) and the recirculating circuit (400, 400a) up to the recirculating valve (403, 403a); f) wherein the recirculating valve (403, 403a) is controlled by the controller to open and allow the refrigerant from the first and second recirculating hoses to recirculate refrigerant to the system oil separator (262, 262a); and g) wherein the controller (216, 216a) is further configured to, after the first time delay, keep the recirculating valve (403, 403a) open such that vapor refrigerant is removed from the first and second service hoses (124, 124a; 128, 128a) and replaced with recirculated condensed refrigerant.