I GOT IT CLEAR!!!!!!! And I used science, chemistry, and engineering to do it.
As I suspected the acid just wasn't getting to the clog because the line was getting air locked so the acid couldn't flow down to it. It didn't matter that I had the acid elevated 3 feet above the top of the heat exchanger/condenser as that just wasn't enough pressure. So I connected a 3 foot hose to the outlet/top side (that would be reverse flow from normal) and filled that line with an acid mixture just like I did all day yesterday. Then with the hose full of acid I connected the
dock water to it and pressurized the line to force the acid down to the clog. In 5 minutes the clog blew out!
To those that truly tried to help, thanks. To those that seemed to think I'm some kind of idiot, .................... well you know! And acid WAS the answer, just like in the manual.
BTW - I've been
flushing that line with
dock water regularly the past 3 months! I've even ran some acid through it.