Your experience in networks is extremely valuable to companies that deal with whole building automation/energy management systems (BAS/EMCS). You will find these in most medium to large buildings, and in campus and industrial settings as well. Go to the big boys' (JCI, Honeywell, Siemens, Andover, Alerton, Automated Logic) web sites and do some research. Do a google search for DDC, BAS, EMCS, HVAC controls.
Most of these systems exist on one network or another with multiple workstations, servers, laptops, etc - and the industry is fast moving into web-based systems and applications. Most control companies (contractors and manufacturer reps/dealers) are ill equipped to handle this part of their systems. You will still need experience in HVAC (alarm priorities,etc) and may likely have to know some about lighting, access control, life safety, etc - but my guess is if you talk to companies that handle these size systems you may find a position that will pay you equal or more than what you are making now.Good luck!