Here is the manual for the R32 Goodman modulating furnace.

NOTE: Supply air and Return air sensors (0130F00933 and 0130F00934) are OPTIONAL accessories, and are not required for the system to work properly. The control board is equipped with an "on-board" sensor, which is used for control algorithms. If a return air sensor is added, the control board will average the 2 sensors and use that value for control algorithms. 

If you are using a non-A2L refrigerant with this furnace, be sure to see our video here below to turn it off.