When I have an SMB volume as a destination, Apple Compressor leaves the temp file after the encoding is finished. The temp files are the same size as the encoded files which range from 50 to 300 MB. I am able to delete the files through the SMB connection from my iMac, I don't need to log directly into server.
I'm using Compressor 4.3.2 on an iMac running 10.12.6. I am encoding to a Mac Pro (old cheese grater) that is running OSX server.