Not used to these new HVAC unit as I am a refrigeration guy. I just installed 2 new units in my parents house. American standard 4a6h6036c1000a paired with the tam7. I am having a problem with the downstairs unit going off on an error code 10, y2 with out Y1. I have checked all wiring and its identical to the other unit that has been running fine. I did have to install the non communicating wiring harness on both units. Not sure what to do at this point, thinking about switching the t stats to see if that is the problem. Brand new t stats though. Let me know y'all's thoughts. Thanks in advance!!