The Different Kinds of Anode Rod
The anode rod is an important part of a water heater that has a tank system. Without this metallic cylinder, the inner parts of the tank will succumb to corrosion and rust build-up. Your anode rod should be annually checked if it’s still able to absorb rust. If the rod has heavily corroded then it must be replaced as soon as possible. Little do people know that there are actually different kinds of anode rods available. Each of them has special properties that make them effective depending on the situation & needs of your heating tank.
Aluminium was the staple anode rod in classic water heater tanks, but its demand was lowered due to some health issues. This is still used today, but mainly installed in heating systems that have hard water supply. There are some issues in drinking water that has high aluminium content since it doesn’t fair well with the digestive system. You can actually use a simple method to check if the anode rod in your water heater tank is aluminium or not. All you need to do is try to bend the steel cylinder, and if it can be easily curved then the anode rod is most likely aluminium. You can always have an expert check it if you want to confirm the composition of the metal.
Modern water heaters make use of magnesium anode rod instead of aluminium since it’s much safer. However, the problem with magnesium is that it corrodes faster than aluminium. If you live in an area where there is plenty of hard water supplies then you’re better off using aluminium since magnesium will expire faster and you need to replace it a lot; which makes it very expensive in the long run. More importantly, don’t install magnesium rods in rusted tanks since it has the tendency to create hydrogen gas which can lead to leakage and possible explosion from a gas reaction.
- Impressed current rods
This is a unique set of anode rods since it’s not prone to corrosion. Impressed current rods don’t have any metal that absorbs corrosion, but instead it uses electricity to absorb degradation. Having no rusty parts doesn’t mean you can just leave this rod alone without any maintenance; it must also be checked and cleaned to keep the electrical charge functional. This rod is mainly used in huge water heaters as it is more effective in dealing with corrosion in large spaces. Impressed current rods are not common in households since it’s very expensive and often found in high-end heating units.
Zinc anode rods are basically hybrids since it has a mixture of both aluminium and zinc, although it’s a bit disproportionate since 1 composition of zinc is to 10 aluminium. The zinc properties actually help in lowering the sulphur odour that can degrade the tank of the water heater. Furthermore, zinc can also reduce the bacteria from iron, which is often the source of the rotten egg smell that plagues water heaters. If you’re having odours in your water heater due to bacteria then you should consider installing zinc anode rods.