On arrival the system was not communicating. I wired all spare wires from all communication bundles back to common and found one of the communication wires “A” not tight at all, completely backed out of the lug which was most likely the issue. I do recommend upgrading the thermostat and zone sensors to the new infinity version For the improvements in technology and aesthetics. System is running and I verified an acceptable vapor line temperature before leaving ensuring unit was not going to freeze due to an unforeseen problem.