I have a existing job that has a Trane Tracer Summit System with 2 Comm 4 Links for VAV boxes, and a Comm 3 Link for PCMs and a Chiller. A contractor just installed a AHU without any controls on it. They ended up hacking the whole install and nothing is working right. I saw the wiring diagram for this AHU/Blower Coil Unit had a ZN520-ZN521 on it. I called Trane and they priced me up all of the necessary controls for this AHU. I am wanting to network this device into the existing BCU. I know that this controller is a Comm 5 controller. I looked at the BCU and I saw that link 4 isn't in use. So I know I can configure it for a Comm 5 link. I just wanted to make sure that I wasn't going to run into any problem trying to network this controller in. I believe this BCU is a BMTW with a version 12 or 13 image/software. Will I be able to use this controller with this BCU? Do you guys have any helpful tips on bringing one of this controllers into a BCU? I haven't had to do this yet. I would think it would be as easy as discovering the device and assigning the neuron ID, but I am not sure.