Why is salt needed in the dishwasher?
Dishwasher users have long been arguing about whether dishwasher salt is needed and why, can it be replaced with regular table salt or is it better not to use anything at all? We decided to express our opinion on this matter, after first understanding the chemical composition of salt and the structure of the dishwasher.
Composition of special salt for PMM
Not many of us will remember chemistry lessons at school, and therefore we will try to explain as simply as possible the composition of dishwasher salt, which manufacturers strongly recommend using.
On packs of well-known salts such as Finish or Somat, it is written that they contain sodium chloride, the chemical formula of which is NaCl. What is sodium chloride? It is the sodium salt of hydrochloric acid. Sodium chlorine is popularly called table salt, the composition of which consists of 98% of it. On a pack of Ecover salt the composition is indicated as follows: evaporated 100% rock salt, which is identical to the concept of “table salt”.
However, in appearance special salt It is somewhat different from ordinary table food, at least in that its granules are much larger and more uniform. But we'll talk about this later.
How salt works
Why is it necessary to put specially treated sodium chlorine into the dishwasher? This is primarily due to the design of the dishwasher and water hardness. Everyone knows that tap water can be very hard, as evidenced by limescale deposits in the kettle, limescale streaks on the taps, etc.
When water is heated to a high temperature, the calcium and magnesium salts it contains precipitate, which we call scale.Limescale will shorten the life of the dishwasher heating element. To do this, a special tank filled with ionized resin was inserted into the dishwasher device. Water passing through the resin becomes softer due to the fact that the positively charged calcium or magnesium ions are attracted to the negatively charged sodium ions in the resin. The water that enters the dishwasher tank is already soft.
Over time, the resin's ability to soften water decreases. To restore it, it is necessary to add sodium ions to the resin, which are precisely contained in salt. If salt is not used, the ion exchanger will soon fail, and the harder the water, the faster this will happen. Thus, salt is necessary:
- to soften water;
- prevent the appearance of scale on the heating element and the inner surface of the tank;
- in order to wash dishes better, because it is known that in soft water everything is washed and washed much more efficiently.
It is mandatory to use salt in the dishwasher, but you can do it in different ways. If the water in your region is soft enough, then salt can be replaced with dishwashing tablets that already contain salt. But if the water is hard (you can find out using a special test strip), then you need to use salt separately. After all, if it is not poured into the ion exchanger, it will become clogged with deposits and break down, since water will constantly flow directly through it. As a result, repairs cannot be avoided.
For your information! In some models of dishwashers, when using tablets, water passes into the machine bypassing the ion exchanger, which will not affect its performance.
When there is not enough salt in the ion exchanger, the indicator on the dishwasher panel lights up.You need to add salt to the tank, the question arises how much? You can immediately pour more, but so that the compartment is not too full. How much salt is enough depends on the quality of the water; the harder it is, the higher the consumption. Using tablets containing salt, the question of how much salt to pour will not arise; there is as much salt in it as will dissolve in one washing cycle. For small dishwasher Such a tablet can be divided in half, but do not crush it into powder.
Special or food: is there a difference?
The need for salt in a dishwasher is more than clear; salt is needed and you can’t do without it, no matter what they say. But is it possible to replace special salt with regular table salt if their composition is 98% the same, despite the fact that table salt is several times cheaper than special salt? But there are still differences between them.
- Firstly, table salt differs in granule size and appearance.
- Secondly, table salt is less purified than special salt, although it is food grade. It may contain inclusions of grains of sand, as you saw in the photo, as well as a lot of microelements: iron, manganese, potassium, iodine, boron and others. Some of these elements will settle inside the dishwasher, which may affect its performance.
- Thirdly, the dissolution rate of table salt differs from special salt. Since it is smaller, it dissolves faster.
If you change the regenerating salt to table salt, then only to “Extra” salt, since it undergoes better processing. But even in this case, before pouring salt into the compartment, look to see if there are any obvious impurities or stones in it.
Important! Table salt should not be poured to the top of the salt compartment, otherwise it may not dissolve at all and stick together.
Thus, you must definitely use salt for the dishwasher, and why and how much, we hope you understand this. What kind of salt it will be, decide for yourself - the one that is more expensive, but probably without impurities, or the one that is cheaper, but with the risk of breakage for the dishwasher.
Interesting:
16 reader comments
Since when do we have sodium ions negatively charged?
For 1.5 kg of finishing salt they are already asking for more than 200 rubles! Good business..
After reading the advertisement for Finish dishwasher salt, we can conclude that this salt is much safer for the person himself, not only for the machine :))
Has anyone tried eating it? What result? What does the manufacturer generally recommend in a situation where Finish dishwasher salt accidentally gets into the food and remains on the dishes?
My washing machine is already 10 years old. I have never used salt. Works like a clock)
I don't use salt, the water is soft.
The article was written by an illiterate manager, not a chemist. This process is called sodium cationization. Sodium ions are exchanged for calcium and magnesium ions, which determine water hardness. As sodium ions are depleted, they must be added to the water to regenerate the ion exchange resin.
Why does everyone write in their publications that the difference between salt is that it is larger. Take “SOMAT” salt - it is very fine, finer than extra salt.
Fine or table salt will clump and not work, while coarse salt will take too long to dissolve.
So is it necessary or not to add salt? I just bought a dishwasher. I use tablets. I hope for your advice.
If the tablets are from Somat, then you don’t have to use salt. And if you take a cheaper option like “Cinderella”, then you need salt.
People, buy salt, which is sold for geyser or other filters at 25 kg for 500 rubles. Savings are obvious.
Which one is for water treatment plants?
I use Finish salt and Quantum Finish tablets. I don't see the point in saving.
They used salt and the machine rotted. Well the warranty has not expired. The service worker was shocked. And he advised not to use salt on the new one.
😀
Well, I made you laugh!!!
I sprinkled coarse salt, which is used for salting fish. 8 years - normal flight, tap water is very hard, a lot of scale.