working on a 5 ton heil cond. unit. unit was installed in new home and before it ever got turned on,it got a hole knocked in the cond, about 1/16.of course lost all the freon and some oil[there was oil residue around cond]. contractor decided he would fix it. so hole was silver soldered up ,and unit is up and running,cools fine but has a high pitch sound coming into the house through the lines.this is a scroll compressor,orig. holds 55oz of there any way to deterime how much oil should be added back in this unit or do you just use a educated guess.looking at the unit if i was to pour 6-8 oz i think it would make about the same mess!i'm thinking this may be why the unit is noisy.any suggestions? thanks lear0