Anode Rod - R-Tech for Tank Type Water Heaters by Rheem / Rudd

The Sacrificial Anode Rod
Designed to prolong the life span of your tank type water heater .

R-Tech - Magnesium & Aluminum Anode Rod by Rheem / Rudd / Richmond.

R-Tech is a replacement for an all aluminum anode rod it may be used in most popular sized, brands of water heaters including Bradford - White, GE, Hotpoint, A.O Smith, State, John Wood, Richmond, Rudd and others. The R-Tech Anode Rod can provide Cathodic Protection for any water heater that has a 3/4" FIP Tank Bung available for an Anode Rod, and that is shaped such that it will fit the 44" long R-Tech Anode Rod.

Fact - When dissimilar metals are in water  (such as copper, brass and steel, all are common component metals used in most water heater tanks and attached domestic hot water pipe systems)  these two results will happen; 

The Purpose of the Anode Rod in a Tank Type Water Heater

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, immersion thermostats, inlet and outlet nipples. 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.

In a water heater, corrosion is protected by a glass (actually a porcelain enamel) lining in the steel tank, and the use of auxiliary anode rods. During the manufacturing process, the inside water tank and both the top and bottom heads are sprayed with a slurry of glass material. This material is fired in a furnace, and when cooled, resembles a glass coating called porcelain. This glass provides a long life to the steel tank; otherwise, the tank would fail or corrode in a relatively short time. Every glass lined water tank, no matter how carefully it is manufactured, has some bare metal exposed. This is due to the inability to effectively cover sharp corners and the radius around the fittings. There is a chance that a crack or chip in the porcelain lining will allow the water to come in contact with the steel tank. Over time, water, a universal solvent that becomes more aggressive with temperature, slowly dissolves the interior tank lining. This will create conditions for corrosion, pinholes in the tank and finally tank failure.

Cathodic protection is accomplished in the glass lined water heater by using an auxiliary magnesium anode. Due to the relative position of magnesium to steel in the electromotive series of metals, magnesium will corrode, producing an abundance of electrons which flow (much the same as an electrical current) to the exposed steel surface and maintaining it in the electro-negative state. As current flow takes place, the anode rod reacts chemically to corrode at a rate faster than the steel inner tank. This process stops tank corrosion by substituting the sacrificial magnesium anode rod in place of the steel tank. As long as the magnesium anode rod remains in the tank, in an active state, there will be no corrosion of the minute areas of exposed steel inside the tank. The life of the anode, in turn, depends on water temperature, amount of water used, and the quality of the glass lining. However, the most important factor in the life of the anode rod is the water chemistry, the hardness or softness of the water. Also, check the manufacture and installation date of the water heater. If the heater is more than five (5) years old, and the anode rod has not been replaced, inspect the anode rod. The anode should be replace when there is six (6) inches or more exposed core wire at either end.

From time to time, questions are raised as to the use of the R-tech, magnesium, and aluminum anode rods. Generally, these questions are raised in areas where some unusual water problems occur with resultant odors. For many years, the regular magnesium anode was and is the standard anode for use in water heaters tanks. In general, it is a very good anode; however, the performance is dependent on water chemistry. In waters where the conductivity is low, the anode operates at a very low current level. This means not much cathodic protection. Conversely, where the water conductivity is high, an excessive amount of current is produced with inefficient operation. This will sacrifice the anode sooner than predicted and require more frequent replacement. In addition, some of these waters have excessive sulfate content along with various strains of sulfate reducing bacteria *. These bacteria, harmless to health, will grow in the presence of the highly active magnesium anode rod and using the hydrogen ion from the anode-cathode reaction, will produce hydrogen sulfide gas. The gas smells like rotten eggs. The greater the activity of the anode, the more hydrogen ions are produced – and the more hydrogen sulfide (smelly) gas. This bacteria can be killed with adequate additions of chlorine, such as with an automatic chlorine feeder. Aluminum has often been used in these types of installations because of the lower activity level of the anode. This is brought about by the lower voltage potential of the anode. Due to these lower levels of activity, lower quantities of hydrogen ions are produced. This reduces or alleviates the odor producing potential of the sulfate reduction of the bacteria. While the problems are reduced with the aluminum anode rod, they are certainly not eliminated. The R-tech anode rod was developed to operate in a broad range of waters without the sensitivity to the various water conditions. The anode, or a variation there of has been used over 15 years in gas water heaters with minimal problems with odors. With the invention of the resistor electric heating element, Rheem now uses the R-tech anode rod in electric water heaters. In doing this, we are now able to efficiently utilize the R-tech anode in all types of water conditions. Because the R-tech anode rod performance equals or exceeds the performance of the aluminum anode rod, we have eliminated the aluminum anode rod from our product line since 1993.

 * Information from RHEEM WATER HEATER Technical Service Bulletin

Anode Rods and Cathodic Protection
Technical Competence, Product Confidence
1201.DOC

FAQs about Smelly Water - Rotten Egg Odor in Water Heaters

My water is smelly and oftentimes has a rotten egg odor. What can I do?

The incidence of rotten egg odor or black water in hot water lines is due to the reaction of sulfates and micro-organisms in the water that create Hydrogen Sulfide (H2S). This is a water chemistry condition, rather than a water heater problem. Although there is very little literature associating odors and sulfate reduction with magnesium, there is reference to sulfate-reducing bacteria known as ‘desulfovibrio’. These bacteria cannot grow in the presence of atmospheric oxygen, which may be why they are not being noticed in cold water supplies. When the same water is heated, they odor becomes noticeable. How can H2S be detected? Just take a swift sniff. A simple check for the cause of the odor is to draw enough hot water to notice the odor. H2S is one of the few water contaminants that human senses can detect at low concentrations. The odor is most noticeable when water is first turned on or heated. A shower can be an unpleasant experience with hydrogen sulfide present. The odor can be detected at levels as low as 0.5 parts per million (ppm). At less than 1 ppm, H2S will give water a musty odor. At 1 to 2 ppm, it will have an odor similar to rotten eggs. Levels are usually less than 10 ppm. The source of the odor is in the cold water supply, such as untreated rural water systems or well water; but does not present itself until heated

What is hydrogen sulfide, and how does it form?

Sulfur-reducing bacteria that are naturally present in ground water use sulfur as an energy source to chemically change sulfates to produce H2S. The bacteria uses sulfur from decaying plants, rocks, or soil. They exist in environments that are oxygen-deficient (not enough oxygen) such as deep wells and plumbing systems. However, H2S can exist naturally in ground water as well. It can enter surface water through springs and quickly escape into the atmosphere. Some of these waters have excessive sulfate content along with various strains of sulfate reducing bacteria. These bacteria, harmless to health, will react in stagnant water that has been depleted of oxygen and will produce hydrogen sulfide gas, utilizing the hydrogen ion from the anode cathode reaction. This problem is more prevalent in softened water containing sodium in place of calcium and magnesium. The anode may have some affect because the greater activity of the anode, the greater amount of the hydrogen ion and hydrogen sulfide gas. These bacteria can be killed with adequate additions of chlorine such as in a chlorine feeder. This will usually eliminate the odor problem. How can H2S be treated? There are two ways to eliminate an odor problem. They are listed in the order of preference.

Two ways to solve a Smelly Water /  Rotten Egg Odor problem in a Hot Water Tank. 

 Chlorination - by means of a continuous chlorine feeder; or periodic flushing with common household bleach. This process is 100% effective only if a continuous chlorine feeder is installed.  

Q: How do I know if the Anode Rod will fit my water heater?

Q: How do I know the Rheem R-Tech Anode Rod will fit my water heater?

Rheem R-Tech - Magnesium and Aluminum Water Heater Anode Rods for are made by Rheem Water Heater**. 

R-Tech Magnesium and Aluminum anode rods are a universal replacement for any, all-aluminum anode rod of the same size.

The R-Tech Anode Rod may be used in most popular sized, brands of water heaters including, Bradford - White, GE ***, Hotpoint, A.O Smith, State, John Wood, Richmond, Rudd and others.

The R-Tech Anode Rod can provide Cathodic Protection for any tank type water heater that has an available 3/4" FIP Tank "Bung" located on the top of the water heater tank and as long as the tank will allow for insertion of  the R-Tech Rod, which is 33" in length.  Check on your ceiling height over the water Heater if the ceiling is too low that can present a problem replacing an annode rod. If too low consider cutting an ez to patch hole in the sheetrock to allow for the installation.

About Branding & Water Heaters

** Rheem Water Heater is owned by Paloma , the following brands of water heaters are also brands owned and manufactured by Paloma and these heaters are made in the same plants by the same folks, so naturally a lot of similarities will exist. Those other brands are;  GE ***,  Hotpoint, Richmond, and Rudd.  Although model names and numbers will be different many of the heaters within these particular brands of water heaters are virtually the same, that is; having the same dimensions, and using mostly the same parts. Warranties often will vary and gas burners and electric water heating element sizes may also vary.

*** GE Water Heaters are available exclusively from Home Depot (in the U.S. and Canada only). GE  is a trademark of General Electric Company and its licensor's.

Here's a link to a homeowner and friends replacing a water heater dip tube and anode rod very interesting and well done photo text blog on how it went.  Thanks !!

Chlorination Treatment of a Tank Type Water Heater

Chlorination Treatment of Water Heater Tanks     

Milky Water in Water Heater Tanks is due to Dissolved Gases!

Water Heater - Dissolved Gasses and Milky Water in Water Heater Tanks

Gasses such as oxygen, chlorine, carbon dioxide, hydrogen sulfide and others are soluble in water. In fact, water is made up of two gasses, Hydrogen and Oxygen (H2O). The amount of gas that water can hold is decreased as the temperature of the water increases. For example, a pot of cold water is placed on a stove to boil. When the pot is first put on the stove, there are no bubbles. As the water is heated, bubbles form on the bottom and sides of the pot. This is the perfect example of gasses, naturally present in the water, being released as the temperature of the water increases.

Another point that is noteworthy is that hot water from a faucet may also expel these naturally occurring gasses. One of the more common occurrences is the phenomenon called milky water. The hot water, when drawn into a clear glass, may appear discolored or chalky. Allow the glass to stand for a few minutes and the water becomes clear. By allowing the water to stand for several minutes, the small gas bubbles, that give the appearance of milky water, will dissipate and the condition will clear. Aerated faucets may help in reducing the likelihood of this happening.

In the plumbing field, we should also be aware of a couple of other effects of this gas release. As pressure inside a plumbing system increases, the waters ability to retain dissolved gasses increases. The higher the pressure, the more dissolved gasses in the water. Significant pressure drops may occur at the inner radius of elbows and fittings under high pressure. This rapid pressure drop may release gas bubbles. These gas bubbles have an abrasive effect on piping and are an important factor in corrosion-erosion.

The release of dissolved gas also creates air pockets and air locks in plumbing systems. The spurts of air or gas when opening a hot water faucet can be attributed to the release of dissolved gasses in the water. Other gases, such as hydrogen, can be a by-product of severe corrosion activity in a plumbing system. Another phenomenon is the incident of smelly water. Smelling like rotten eggs, the gas is really hydrogen sulfide. It is at the point of pressure release, due to the increased water temperature, that noxious gases like hydrogen sulfide become noticeable. The sulfate reducing bacteria that form the hydrogen sulfide gas may have been absorbed by the ground water and are present in both the hot and cold water. However, due to the hotter water, such as in a water heater, the gasses are released and more noticeable when one is taking a shower. The percentage of gasses that can be held in water lessens as the temperature increases. For example, at freezing, 100% of the existing gasses in the water can be retained. As the temperature of the water increases, the ability of the water to retain the gasses will decrease. At 70F water will hold about 60% gasses, at 100 F water holds about 46% gasses and at 140 (a normal setting for domestic hot water) about 36% of gasses are contained in water.