Here is some background on myself before I ask my question. I am an HVAC apprentice in my 3rd year of school. Before I became an apprentice I worked in a few different supply houses, so I have a pretty good understanding of the basic principals of HVAC/R. However I know I have a whole lot to learn.
I have an in-house position that I've had since I started my apprenticeship. I work on WSHP from 2-10 tons, RTU's from 2-20 tons, splits from 2-100 tons and various other types of equiptment. I feel like I am limited in a way that I have been working on the same units for the past 3 yrs. I am looking for any advice on ways to learn ( books, websites, ect.). I know trial and error is the best way to learn, but most of the time you have to wait for something to fail before begining trial and error. I would be interested in learing other types of the buisness aswell such as sales or engineering. Obviously learning service work is more applicable now but eventually I would like to not have to carry around a tool bag and climb ladders if you know what I mean. Any advice would be greatly appreciated.