Keeping track of a plumbing infrastructure is a tall task when you’ve got a lot of other things going on. You probably want everything working without having to think about it. This is a reasonable expectation until one thing goes wrong. Much of the time, everything will function without an issue; however, especially during the coldest phase of the year, you need to be on top of any conceivable failing. An anode rod is an aspect of a plumbing apparatus you may forget.
In fact, you may never even know about one until it’s presence is obvious, which is usually a bad thing. Let’s change this for the better. An anode rod––a sacrificial anode rod (sacrificial is a functional modifier)––is an essential component of a water heater. Although a anode rod is not a factor in heating anything, its degradation actually enables a water heater to continue its job for a lot longer than without one.
Anode rod composition
An anode rod is made of either aluminum, magnesium, or zinc, and surrounds a steel wire inside of it. Depending on the size of the water heater, anywhere from one to five of these will be fastened into the top of the heater. The general purpose of an anode rod is protecting the rest of the water heater from rust and corrosion. Usually, the tank of the water heater is made of steel, which is less reactive than the material on the outer cylinder of the anode rod.
Now you may begin sensing the value of the ‘sacrificing.’ Eventually, the rod itself decays and will need a replacement––after which your water heater may continue on indefinitely. Assuming, of course, you replace recurrently. If you fail to replace an anode rod, your water heater will succumb in the same way. Unless, of course, you have a tankless water heater, in which case you won’t need an anode rod in the first place.
The heater is susceptible
In the many years before tankless water heaters, however, manufacturers faced a difficulty insofar as the gases of water, like carbon monoxide, make H2O acidic. The combination of oxygen, moisture, and the substance of the water heater induces corrosion and rusting, which is only accelerated by the heat of the heater itself. Moreover, the various elements of the water heater also produce an electrically conducive environment, another accelerant.
Chemically, the activity involves oxidation, in which iron dispenses of two electrons after interacting with oxygen. The same is also true of aluminum, magnesium, and zinc, except the process goes a lot faster. As a result, as the oxidation occurs, the oxygen removes the electrons from the anode rod instead of the water heater, which is expected because the exchange always precedes any corrosion off the water heater. This is the sacrificial aspect of the anode rod.
Check on the anode rod every three years
It’s giving up electrons in order to save the water heater from giving any up itself. Naturally, you’ll be checking in on the anode rod with a measure of regularity in order to prevent an expense on an unnecessary new water heater. The regularity of replacement hinges on a variety of qualification, like water temperature, quantity of usage, efficiency, and fluctuations in chemistry. Generally, you should check on the anode rod once every three years.
Consider a powered anode
Finally, a water softener will also increase the rate of decomposition of the anode rod. If you decide to implement a softener, be aware of the accelerant and check earlier, often as much as every six months. One alternative is a powered anode, usually over $200, which reduces the rate of deteriorating by giving off an electrical current. For reference, a common anode is between $45 and $75.