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What is a Sacrificial Anode Rod?

When it comes to your water heater, it has a single primary function—it heats water. It does it fairly well, the majority of the time, and it by conducting the heat throughout the metal. It then warms up the water that goes through your house when the tap’s turned on. You also know that water will rust metal.

The reason that your water heater isn’t fully of rust is due to something small and amazing: the sacrificial anode rod.

How Do Sacrificial Anode Rods Work?

Metal corrodes due to three things: steel or iron, water and oxygen. These are all contained in your water heater’s tank. Even though the more modern ones have their tanks enclosed in glass, it’s still possible for water to seep into the cracks which can rust the tank. Therefore, these rods are put into the tanks. They’re made of aluminum or magnesium, both of which are less noble, meaning they quickly rust in water.

Rusting begins with oxidation. This is when the iron loses two electrons to the tank’s oxygen. When you place an aluminum or magnesium rod into the rod, this also will happen but a lot faster. The bonds that that are between the aluminum and magnesium molecules will release the electrons much faster than those in iron or steel. Therefore, when you an anode rod made of one of these two metals into a steel or iron tank filled with water, the electrons from the rod are taken rather than the ones from the tank. Therefore, the rod’s rusted rather than the tank.

If you’re looking for a simpler answer, the rod’s going to rust a lot faster than the tank’s steel or iron. This means that the tank isn’t going to rust until the rod’s totally rusted away.

How Long Do Anode Rods Last?

There’s a reason why these are called sacrificial anode rods: they sacrifice themselves to save the tank’s lining.

Eventually, all of the rod’s metal is going to rust completely away. That means that there won’t be any more electrons that it can give up for saving the electrons of the tank to keep it from rusting. When your anode rod’s rusted away, your tank might start rusting. This is going to cause your water heater’s failure. This means you are going to have to replace your water heater. This is why it’s so important for you to check or replace your anode rod every few years. Look at the recommendations of your manufacturer to see when your tank is going to need its anode rod changed.

Signs You Need a New Anode Rod

Sometimes you may not know when your anode rod needs to be replaced. So here are some signs that you should check it and possible replace it.

  • The pan of your water heater’s started accumulating water
  • You’re looking for a way to extend your water heater’s lifespan. Anode rods are a lot cheaper than new water heaters.
  • You are using a water softener, since they can accelerate the corrosion of your anode rod.
  • Your water is acidic, since this can accelerate the corrosion of your anode rod.
  • Water softeners can accelerate anode rod corrosion.
  • Acidic water can accelerate anode rod corrosion.
  • Your water heater’s making multiple popping or loud noises when it’s heating up, since this can signal that your tank lining’s potentially corroding.
  • The last time you checked or replaced your anode rod was 3 years ago
  • Your faucet aerators are clogging more frequently
  • You clean your faucet aerator and there’s a substance that’s slimy and gel-like.
  • Bad smelling, sandy or gritty water.
  • Your water heater bills are high. An old rod will increase how much sediment is at your tank’s bottom, and this will inhibit heat transfer.

If you have a warranty in your home that protects your appliances and systems in the home, you should know that it won’t cover your water heater if it rusted due to the rod not being maintained. But if it fails due to passage of time and normal use, it will be covered. You just have to pay a service fee even if it has to be replaced.

If you are noticing any of the problems above or you have any other questions about a plumbing problem, please get in contact with us. We are always glad to answer your questions and put your mind at ease.