I remember recently reading a thread on here somewhere that stated that you should run the cold water and the hot wort side-by-side through a plate chiller; but every diagram and label I had seen for plate chillers ALWAYS shows them running in opposite directions.
I now have confirmation that these should definitely be used in opposite directions and a description of WHY this is: http://www.homebrewtalk.com/f11/attn-engineers-plate-chiller-parallel-perpendicular-flow-427742/
Adam
Counter flow.
I tried it the wrong way once(by mistake) and it took me a while to figure it out. Changed the flow over and it started working again.
Nice to have you back Adam!