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Aluminum Anode Rods vs. Magnesium Anode Rods

In 2014 Heat-flo, Inc. began producing all products with magnesium anode rods as a way to combat corrosion in aggressive water situations. The magnesium anode rods worked very well, as we expected, but they didn’t last as long as we felt they should and actually caused an annoying issue for the homeowner. That issue was a burst of air when the hot water was initially used after hours of being idle. 

After much research it was determined the use of an aluminum anode rod will correct the burst of air problem most of the time, and they last longer. As a result of this research, we began producing products with the aluminum anode rod toward the end of 2020.

Both the aluminum and magnesium anode rods are currently available, though the aluminum anode rod is the preferred choice. To identify which anode rode you have simply look at the face of the brass nut on the anode, if you see an “A” stamped into the front of the brass nut you have an aluminum anode, if the face of the nut is blank you have a magnesium anode. 

If you have experienced issues with both types of anode rods, the unit may be run without it. We only recommend this if you know your water. Just because you have city/town water doesn’t mean the water is OK. Municipal water suppliers must meet regulations that have chloride and pH limits much higher than what the warranty on your unit allows. Aggressive water as it relates to stainless steel is water that has a chloride level equal to or greater than 100 parts per million (PPM), and a pH lower than 6 or higher than 8. Check with your city or town for a copy of the most recent Consumer Confidence Report. DON’T ASSUME YOUR WATER IS FINE!