Greetings one and all, I'm new here and I'm almost finished with my HVAC/R course at Penn Foster so I'll be entering the field soon. I have two questions: first, will someoneplease offer me some suggestions on what permissions/memberships I should request in order to use this forum as a professional starting out? Second, my dad had his AC replaced a few years ago by a very reputable local company and dad told me last week that they intentionally installed a 3.5 ton compressor and condenser with a 4 ton evaporator. Everything I've read says that all components should be properly matched. Are there instances where a mismatch is warranted or was this just a less than optimal installation?