Everything needs to be known about the anode in a water heater, its properties and principle of operation, because it affects the service life. If you do not change it, this has a bad effect on the duration of the boiler. What is it, what is it for, and how to perform a replacement, read below in our article.
The purpose of the magnesium anode
It protects the tank from corrosion and takes care of all the oxidation processes. Let's consider how storage water heaters function, in more detail.
Tanks of boilers "Termex" or "Ariston" are made of stainless steel or covered with a protective layer of enamel. According to the statement, stainless steel is not susceptible to corrosion. But the following points should be considered:
- The case is made of food stainless steel. The material is not able to withstand oxidation for more than six months. If the manufacturer used high-quality steel for manufacturing, the cost of the equipment would be too high.
- The tank is not created whole. It mainly consists of two parts that are connected by seams. Under the influence of high temperatures, the joints can be deformed, which leads to the loss of properties of the stainless material.
What else do you need to know? Manufacturers are trying to prevent a reaction by covering the inner walls with protective agents. Over time, they also lose effectiveness. When heated, water expands the metal, so the alloy is stretched, losing properties.
After the formation of microcracks, oxygen oxidizes the metal, which leads to irreversible corrosion.
The metal housing and the heater create a galvanic pair. The case in this case acts as an anode. So that it does not deteriorate when exposed to water, manufacturers installed an alloy, which includes magnesium, next to the heating element. It takes on the role of the anode - as a result, all the oxygen goes to its oxidation, and the tank remains intact.
Over time, the alloy is destroyed, its particles settle to the bottom of the body, so you need to periodically put a new one.
Almost all brands of Polaris, "Combustion", "Electrolux" include magnesium anodes in their models. How do they look? This is an alloy on a stick with a flat surface. During operation, corrosion begins to corrode their surface.
Why choose magnesium
Is it really impossible to make an element from other materials? In fact, the cost of magnesium is low, which allows not to increase the cost of the finished product. It also has a weak electrochemical potential. Magnesium attracts salt from water, preventing it from settling on other parts.
What is the life of the anode and how often to change it? Experts recommend replacing every year.
Signs when it is time to change the part:
- Noise is heard during operation.
- The water got an unpleasant odor, became cloudy.
- Long heating.
- Frequent activation and deactivation of the boiler.
This also indicates that the heating element is completely covered with scale and needs cleaning.
You can perform it at the same time as replacing the anode.
How to replace a magnesium anode with your own hands
Consider how to unscrew parts yourself:
- Disconnect the equipment from the network. Turn off the machine if contacts lead to it.
- Drain the water. The fastest way to do this is through a check valve. Turn off the water on the main valve, unscrew the water hoses and turn the check valve.
- In Gorenje models, the magnesium part is located on top. In order not to remove the boiler from the wall, simply pry off the top cover. If this is not possible due to the proximity to the ceiling, you will have to remove the case.
- In other models, you need to remove the bottom cover. To do this, unscrew the fixing bolts and remove the latches.
- If the heater is mounted on the flange, unscrew the nuts and screws, pull out the flange. Sometimes the heater must first be pushed in and then removed from the tank.
- The anode is twisted out of the stand next to the heater.
How to choose a new item? If you do not know how to replace the old one, take it to the store. The part must be selected according to the diameter of the thread. For example, in Thermex Flat Plus, the number is M4.
Install in the reverse order.
How to extend the life of a water heater
Monitor the operation of the boiler in order to detect and fix the problem in time:
- When the water is taken, a hissing sound is heard? So, the heater is covered with scale. You need to clean it.
- It is advisable to install water filters. They reduce the concentration of impurities, which subsequently settle on the parts.
- Sometimes look under the housing cover to check the condition of the anode. If he is half worn out, a replacement will soon be needed.
- If you removed the old one, but did not manage to install a new element, do not start the technique. Buying a new item will be cheaper than buying a new boiler.
- Frequent use leads to rapid scale formation. Therefore, it is recommended that you clean the tank once a year.
Decided on an independent replacement? Be sure to unplug the heater and drain the water. Then proceed with the repair. A video about replacing this part in a boiler will help you: