Found this on the AgTalk wiki page. Revamped my 4450 and had never done any ac work before. After reading this and watching a bunch of YouTube videos I decided to tackle it myself. If you nevere try something you will never learn. Sometimes it costs you money but sometimes it works out good.
And many times you will easily pay for a harbor freight vac pump , gauge set , how to book and a few tools on the first job you do yourself.
4430 AC charging
