i started workin as a helper about a month ago, and the problem is everyday, they send me with different people....so i am confused as how is the right way to do some things..first of all ..after system is pumpdown , and u have soder , and want to test for leaks....do u connect low side or high side? i have seen them do both....and esch gives me a different explanation....second thing when doing duct work before u connect the flex to the collar do u have to mastyc the inside and then put the strap...or just the strap will do? thank