I have a Carrier model #58dr075-ba. I can not locate where the filters are to change them.

Thanks

The filer is located in a compartment where the return air plunum comes back to the furnace. The filkter is in a slide out like drawer. If you aren't sure which is supply and which is return just raise the temp setting on your thermostat. The supply gets warm and the return does seem to do anything.

Try the blower door, I need to know if it is an upflow or downflow furnace. Filter could be in the side of the return drop, up above the blower, in a downflow furnace, or maybe if you only have 1 return air grill it could be in there.