Domestic water heaters are our salvation and a source of comfort: at any time of the year, regardless of the heating season, we can enjoy hot water. But, like any device, these devices need preventive care and repair. And since they are operated quite actively, they must be repaired and cleaned often: once a year. Sometimes after the next inspection you are told that you need to change the anode. What is it and why change it? Let's get it right.
When water is heated, the process of oxidation and destruction of the inner surface of the tank occurs. Most water heaters are available with iron tanks, sometimes they are enameled inside, sometimes made of stainless steel. But in any case, water finds its way to the metal: through microcracks in enamel or through a seam in stainless steel (under the influence of high temperature during welding, most of the properties are lost). Oxidation occurs, salt deposits accumulate, the metal rusts. This can lead to destruction of the integrity of the tank.
To make the process less active, manufacturers use a magnesium anode. For a water heater, it becomes a kind of antivirus. Magnesium contained in this device reacts more actively with the oxygen contained in water than iron. The main part of the salts dissolved in the water settles precisely on the anode, and the salts are more friable and easier to clean. So, a magnesium anode for a water heater is a way to protect the tank from scale formation and destruction. If you have a water heater installed without this device, you can install it yourself.
Magnesium anode for a water heater: types
Most often, these devices are made in the form of a metal rod, on one side of which there is a special threaded rod. On the surface of the pin is applied 10-15 mm
magnesium alloy. Usually it is installed next to the heating element, but sometimes manufacturers put it in another place.
The magnesium anode for a water heater can be of different diameters and lengths, but it is advisable to replace the damaged one with a similar one. For example, there is a special Termex magnesium anode, which is installed in the water heaters of this brand. In some cases, you can try to install a pin of a greater length or thickness, but only in cases where there is room for this. But there are exceptions: Ariston recommends installing a magnesium anode only of its own production and only the size that came in the kit.
Recently, there are some new models that can be installed in any tanks. For example, in low rooms in a large-sized tank it is problematic to install a meter anode (tank height - 1.2-1.7 meters, plus a pin more than a meter long). In this case, it is convenient to install multi-section models. Such anodes consist of several elements of small length, movably fastened together. Conveniently enough, although it requires certain installation skills.
A flexible plastic anode has recently appeared on the market. It consists of a hollow plastic tube with microscopic pores, in which granules of magnesium are filled. Its first advantage: the absence of oxidized magnesium, which usually settles in the tank. Its second plus is the ability to add powder during operation (it is sold separately).