Most of the manufacturers' product specific training "away" classes that cost $$$$.$$ may be way over your head until you get some hands-on wrench time and a sound understanding of the basics. If you haven't already, hook up with a local contractor that does heavy commercial/industrial HVAC and chiller service. This may prove easier said than done in some areas.
Another good for you to do is find the local Trane office and see what kind of training classes they offer. I am absolutely serious about this. The classes that are put on by the local offices are a great value, can be a great introduction to the basics, and they usually supply you with a lot of literature.
The key to happiness is lower expectations.
Don't pick the fly crap out of the pepper.