I spent a lot of time using a kerosene-fired pressure washer that would either steam clean or power wash with hot water, depending on the thermostat setting the machine got. It did a far better job of cutting crud than the cold water machines do these days. Since the tree huggers started writing all sorts of regulations for cleaning detergents and methods, getting anything really clean has become a problem. I live out in the boondocks in sight of two county lines, so I pretty well do what I please, including using a box of Tide and a couple of cans of lye in a wood fired boiling tank for degreasing. Hot water power washing would just be one more tool in the box.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!