There are too many different opinions on proper charging methods for coolers and freezers. I have heard 20 degree superheat at the compressor, clear sight glass, I've even heard someone say you can go as low as 5 degree superheat at the compressor for freezers. I want to be the best Service tech I can be and do it the right way. Can some of you guys tell me the proper way to charge for both TXV and cap tube systems for freezers and coolers. I am very interested in learning correct way.