Ah! Your post made me do a double take. When I first saw the title, I read: Declassify / descale.... then I started reading your post and I kept reading "declassify"... How in the world do you "declassify" a water heater system? Then it dawned on me what you actually typed. I think I've had too much of this "political" stuff in my head lately!
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2019 Montana High Country 375FL
2014 Chevy Silverado Duramax, 6.6L Dually