I went googling for hot water phobia and the first relevant thing I found was this hilarious scary post by Miss Scotch.
Then I found this wonderful wedding webpage by Chantel Kielty, who first took an interest in her future husband when he refused coffee, tea, or cocoa - because he disliked hot liquids.
I still haven't found a scientific-sounding name for this particular phobia. I guess it's on the rare side. And it's not really debilitating, although it would prevent one from working at Starbucks!
I've developed some form of it myself - particularly pertaining to handling hot liquids in open containers - the worst sort being flexible paper cups without tops - and the worst situation being that of taking such a cup from another person's hand. Yes, there really is some risk of a burn or spill, but my reaction is exaggerated. Of course, getting nervous actually increases fumbling in such situations! So I did some reading on phobia treatment and now I'm working on step-by-step desensitization. So far, so good.
Better not to steer
By exaggerated fear.