This is probably a very long shot and a cheeky one at that!
QA Graphics do some awesome HVAC plant graphics. AHU's, Boilers, Chillers, Heat Pumps etc. To purchase their full commercial graphic package will cost you around $4,000. Does anyone have these graphics and are they willing to share or know where I could get them from? They are very good but $4,000 is a bit much.
I guess if you don't ask you'll never know!