Just wondering how long do you leave the pump on the condencer? For 1.5 and 2 T I usually leave the pump on for about 20 to 30 min. Yesterday and today I installed 3 - 5 tonns and 3-4 tonnes at a new building . Tomorrow I'll vac them out for about 30 min each. If you don't mind me asking, what's your prefrence and why?