I've got what probably amounts to a really dumb question, but here goes.

In an upflow furnace is the blower located below the heat exchanger? In a downflow furnace is the blower located above the heat exchanger? Do I have that right? Or have I gotten the two confused? Or am I just confused in general.

I'm new to the industry, and my boss isn't always overjoyed at answering my questions. (....and yes, I'm looking for a more understanding employer)

Sorry to make my first post a really dumb one, any help would really be appreciated.