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All you need to know about Anodes in Water Heaters | Anodes Australia

In this blog, we take a look at Anodes in water heaters. Read on to find out more.‍..

What are water heater sacrificial anodes? It’s quite simple (and effective). Steel and other metals corrode when they come in contact with elements like water. By attaching less noble metals to a steel water tank to attract the corrosive elements in the water, these rods become “sacrificed” units for the overall preservation of your steel-lined water heating tank.

Without this cathodic protection system, a water heater tank becomes vulnerable to rust, corrosion, and many other damaging chemical and mineral effects of being in contact with your water supply. Pretty cool right? But how does it work? Let’s start at the beginning!

What is a Water Heater Anode Rod?

Sacrificial anodes are usually made from relatively pure and active metals, such as magnesium and  aluminium. These more active metals (the anodes) are moulded into rods that oxidize and corrode much faster than the less active metal of the water heating tank (the cathode). These rods serve as a decoy for corrosive compounds – encouraging corrosion on the rod itself instead of on the interior of the hot water tank.

Each of the above-mentioned metals has different advantages and disadvantages for various types of hot water anode applications. In terms of household water heating systems, the below generally applies:  

Do All Water Heaters Have Anode Rods?

Instant water heaters don't have anode rods, but standard heaters will use this type of corrosion prevention. Cutting to the chase, anode rods exist to extend the life of water heater systems and preserving this is a priority for most homeowners and businesses. There's just one problem with the standard rod, it isn't designed to last as long as the water heater itself does. Therefore, proper water heater maintenance involves faithfully checking these, and replacing them as necessary – no one wants a rusty tank that randomly springs leaks.

How Often Should You Check An Anode Rod?

Generally, you should bring in an expert to check your rods every 3 to 5 years. The exact cadence will be determined by a plethora of factors, including whether you have a hard or soft water heating system. When you check your anode rod, you'll probably see some pitting and maybe even tiny holes. Don’t worry, that's exactly what should be happening. However, a rule of thumb is to inspect your anode rod right away if any of the following applies:  

However, to keep protecting your tank, the anode rod must be replaced if the steel core becomes increasingly visible. Delaying is never a good idea because operating a water heater with a depleted anode rod can potentially halve the overall lifespan of your unit. This will incur a great cost to replace each time.

How To Tell If An Anode Is Depleted?

To determine if you need to replace your anode rod or plates, an expert will remove it from the tank and examine it. As mentioned, your anode rod should show signs of use, and look slightly worn through. However, the trained eye will identify all manner of other deterioration factors. For example, if the rod consists solely of steel core wire, as a result of corrosion, you should definitely replace it immediately, although the tank's lifespan may still be over.

What is the Best Way To Replace A Hot Water Anode?

Monitoring and maintaining is the best way to extend the life of the hot water system and enhance its overall operating efficiency. For example, a water heater tune-up includes annual steps like flushing the tank alongside checking for anode durability.

As far as anode installations in Australia go, we highly recommend trusting in a professional with the right type of training and expertise to get the job done quickly and safely. Water heater anodes all serve the same basic purpose, but there are a few models on the market, so you will need to know what kind of anode rod your specific water heater uses first. Speak to our experts for speedy and reliable assistance!

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