System is working fine, found zone damper for upstairs not opening zone board is intermittent Bypass damper is weighted and was taped closed causing DAT sensor to shut down system. Need to replace 14†and 12†zone damper with 12†bypass damper Need to replace zone control with new 2 zone, zone board and DAT sensor . Remove DAT sensor from supply box and put between coil and blower . Prepaid by. Credit card with full amount