A benefit of the Atwood Water Heater is that it's built with an aluminum tank so there is no need for an anode rod. Here's a link to their web site with information, owner's manuals, and other downloads.
That is great. I had to replace my previous camper's anode rod every other year. I had noticed this sometime ago. I read another post that jarred my memory and motivated me to post this question.
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2011 Lacrosse 318BHS Touring Edition
2012 Ford F150 SupCrew 4x4 XLT 6.5' Max Tow