Have you EVER in your life cleaned out a hot water heater? If I cleaned one after a few hours operation I'd expect it to be like new.
DOH.. Production water heater built on assembly line runs at 170 Fahrenheit. DOH.. prototype E-cat (you keep forgetting the prototype part) runs at significantly greater temps. and have you EVER seen any of Thomas Edison's prototype light bulbs? They don't look anything like what we have off of production lines today..
Then it should be built accordingly. If those are deposits, that thing isn't going to last six months. I'd expect that a prototype so close to production would be similar to a unit being sold, especially with the availability of today's materials.
BTW, Rossi can barely make water boil, so the temperatures wouldn’t be much great than a water heater.