Legal Removal Request

Post: i am trying to read pt100 RTDs using channel 1 and channel 2 . I have tested everything using excel and external voltage outside of Raspberry Pi and expended Pi I am getting perfect temperature measurements using Wheatstone bridge and callendar-van dusen equation when I measure using my digital multi meter. I believe that when connecting to expander Pi I need to join both grounds , (I am using 2,5Volts constant power & of course removed jumper) and output to pin#1 & #2. I tried that but got readings close to Vref that was kept at default 4.096V initially in the program, it read 4.095V when I ran example program. Can someone share application notes on it? I tried to put Vref =2.5 too but reads similarly close to Vref 2.499 When I ran program. By multimeter it reads 0 .538V. I have not connected anything to pin 15 Vref