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What Is an Anode Rod? What Does It Do?

tankless-water-heaterTankless water heaters are a great technology. They are compact, they are efficient, and they boast truly staggering lifespans. They still are not right for everyone, though. You see, tankless water heaters are also a much more substantial initial investment, and they can be overwhelmed in scenarios where a standard, properly sized tank water heater would fare much better. All that being said, there is one problem unique to the tank water heater that the tankless water heater does not and could not face.

That problem? The corrosion of the tank from the inside out. Why can’t a tankless water heater suffer this cruel fate? Because they do not have tanks, of course! Don’t take this to mean that you need a tankless system if you want a water heater that will last, though. There is a specific component designed to protect against this type of corrosion, and that is the anode rod that resides within the tank of standard water heaters.

How Does an Anode Rod Work?

An anode rod is also called a “sacrificial” anode rod, and that moniker makes a whole lot of sense. Basically, the whole point of the anode rod is to allow itself to be destroyed. Why would you want to invest in a part literally made to rot away? Because it’s better that part than your water heater tank, right?

Most homeowners understand that metal + water = corrosion. The interior of water heater tanks are lined with glass (some newer models may use plastic, with some of those boasting that they don’t need anode rods at all, but that’s a whole different topic). Now, this coating is an effective way to protect the tank itself, but only to a point.

Over time, cracks are going to start to form in that glass/porcelain liner. Heat will do that, regardless of how well-made the tank is. Once that happens, the corrosive elements in the water can start to attack the tank. However, they’ll attack the anode rod first, because it is made of materials specifically used due to the fact that they attract those corrosive elements. It sacrifices itself so that your tank may live. Okay, that’s a dramatic way of putting it, but it’s true!

So, Why Is the Tank Still at Risk?

Doesn’t all this mean that there should be no risk of corrosion, then? Not exactly. Over time, that anode rod is going to corrode away to a point where it will be practically gone! That will leave the tank at risk. This is precisely why it is so important that your anode rod is expected regularly, as suggested by its manufacturer, and that it is replaced when necessary.

To ensure that this is the case, just schedule service with a member of our team. We take your satisfaction with your water heater and our service very seriously, and we’ll help you to get the most performance possible from your system for as long as possible.

Schedule your water heater services with Foss Heating & Cooling.

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