Why Do Water Heater Anoides Deteriorate So FAST?

in a nut shell, the harder the water, the less life in
the anode rod.

water can make a HUGE difference in anode life. there are areas where anode rods in TT or homes will last a year or less, other places where they last a decade.

We happen to have very soft water naturally and anode rods seem to last a long time in our area. When we lived in MT and ND entirely different story.

Probably due to quality of water supply. Are you on a city water supply?? They are usually better regulated as to acidity and chemicals. My Anode rod looks good each year when I take it out, If it is corroded, I usually wire-brush it and make sure its not eaten through anywhere. Only time I replaced one was when I lost it during the winter.

Link works for me......:H

Anyway here is a clip with pertinent info:

TECHNICAL SERVICE DEPARTMENT
Anode Rods, Cathodic Protection and the Porcelain (glass) Lining

Corrosion can be defined as the destructive attack of a metal by an electrochemical reaction with its environment. Steel exposed to moisture and oxygen will rust and corrode. Corrosion is defined as the ‘eating away’ of metal by electrochemical means. There are four main factors affecting water’s ability to corrode:
1. Acidity - Water is made acidic by naturally occurring dissolved gases such as carbon dioxide.
2. Temperature - Higher temperatures speeds up the corrosive process.
3. Amount of dissolved oxygen - Free oxygen dissolved in the water promotes corrosion.
4. Electrical conductivity - The more dissolved mineral solids in the water, the greater its ability to carry electrical current. When dissimilar metals are in the water:
•Electrical current flows between metals
•One of the metals gradually corrodes faster than the other
Dissimilar metals are present in the interior steel tank surfaces of all water heaters in several forms such as the drain nipples, heating elements, inlet and outlet nipples, and immersion thermostats. These metals, and others present in the water itself, combined with the oxygen content of the water and heat, establish an environment conducive to corrosion. The dissimilar metals create a corrosion cell that is enhanced by the conductivity of the water. The anode is installed to overcome (neutralize) the corrosive cell.

Link does not work for me either, it might be a problem with Rheem's server ... it appears to be a huge PDF document

Google cached version

OB, that link won't totally load for me, maybe it's just me.

As stated, the tank and it's electrical bits are grounded but that wouldn't effect the reaction with the anode rod. The anode is sacrificial, the reaction is based on the free ions in the water of the tank from mineral in the water and the material of the anode. The anode rod would undergo this reaction if it was placed in a glass jar with water (just less so).

Instead of paraphrasing I will just give you a link that explains it all......LINK

Aluminum type rods last the longest BUT can get a build up of scaling which can make them difficult to remove.
Magnesium type rods deteriorate quicker BUT can react to microbes in water and cause a sulfur like smell

Suburban Brand have a steel tank that is glass-lined and therefore need an anode rod to help keep tank wall from deteriorating

Atwood Brand use an aluminum alloy tank so no anode rod needed


Your water heater IS grounded otherwise the propane & electric systems would not function. Further grounding of tank will not stop the 'galvanic' action going on inside tank between tank wall and the water

I need to go back to my science class to research this one....