How to find out the hardness of water for a dishwasher

For a dishwasher as well as for a washing machine, the stiffness of tap water is a very important condition for the washing result. Manufacturers of tablets and dishwashing powders claim that they soften water, but in practice this is not always confirmed. The fact is that the water hardness in different cities of the country may differ, and one tablet in the fight against this may not be enough. Our story will be about how to find out the hardness of water and how to soften it for a dishwasher.

Hard water: how it affects the dishwasher

Water is called hard or soft, depending on the chemical composition of the water. A high concentration of calcium and magnesium salts indicates that the water is hard. Moreover, in chemistry there are such concepts as “temporary” and “permanent” water hardness. The presence of calcium and magnesium salts in water is just a temporary hardness, since when heated, these carbonates decompose and turn into a precipitate.

Constant hardness is characterized by the presence of phosphates, nitrites, sulfates and silicates of sodium and calcium in water. These compounds do not decompose upon heating water and are present continuously.

Important! The degree of water hardness depends on the soil composition of the region. The more calcareous rocks in the soil, the greater the water hardness.

The presence of all of these substances in water negatively affects the operation of water heaters: kettles, washing machines and dishwashers. The greater the hardness of the water, the more precipitate is formed when the water is heated, the faster the heating element can fail. That is why in modern dishwashers, an ion exchanger began to be installed as a water softener, inside which the resin attracts calcium and magnesium ions, making the water softer.

However, over time, the ability of the resin to soften water decreases and if it is not restored, the ion exchanger will fail, and the dishwasher will stop washing dishes. Only the unit replacement will correct the situation. To prevent this, it is necessary to measure the hardness of the water, this can be done even at home.

We determine the hardness of water

There are several ways to determine the hardness of water, some of them are based on everyday experience, others are more accurate and reliable. We list them:

1. Compare the mass. The method consists in comparing the mass of water from different sources. Two containers of the same volume are filled with different water and weighed. The smaller the mass of water, the softer it is. Perhaps this helps to understand what is the hardness of the water, but for a dishwasher, the method is not suitable.
2. Determine the degree of soapiness. It is enough to take ordinary laundry soap, moisten in water and soap your hands. If foam is easily formed and difficult to wash off, then the water is soft. In hard water, soap foams with difficulty. This method is also subjective.
3. The rate of scale formation. Another indicator by which people determine the hardness of water. If sediment and scale accumulate very quickly in the kettle, then the water is hard.
4. Turbidity of the water. Hard water or not can be understood by the turbidity of the water, for this purpose it is collected in a transparent bottle and removed for 2 days in a dark place. If during this time a haze and film formed on the walls, then the water is hard.
5. We use test strips. Such strips allow you to determine more accurately the hardness of the water. In some Bosch and Miele dishwashers, the strips come with the machine. Some strips are saturated with a special composition, it is enough to lower such a strip into water for 1 second, and then compare the result of color development on the strip with the table, for example, presented below.
   
   Test strips from the company "Biosensor Aqua" work a little differently.After staying such a strip in water for 2-3 seconds, you need to wait 60 seconds and only then, comparing with the color scale on the package, determine the hardness of the water. The scale looks like this:
   
   There are also such strips, the use of which requires special reagents. A small amount of water is poured into a glass and a strip is lowered, and then a little bit of reagent is added to the water. When color appears on the test strip, the hardness of the water is determined from the table. With such strips there is a detailed instruction for use, so do not be lazy to read it.

   Note! The method with test strips is the most optimal for home conditions, they are not expensive and the accuracy is much higher than when determining the stiffness by the methods described above.

6. We measure rigidity using a TDS meter. With such a device, you can find out the exact indicator of the water hardness level in the tap. However, the device is quite expensive. If this does not bother you, you can get such an assistant.
   

What to do after measurements, how to soften water?

After you find out the hardness of the water in your home, you need to think about softening it, because too hard water can not only be poured into the dishwasher, but you will not drink. How to protect the dishwasher? First of all, do not forget to fill in time regenerating salt into the dishwasher compartment at the bottom of the chamber. It is very important to adjust the salt flow.

To do this, we determine the flow rate according to the table, which is in the instructions. We offer an example of a water hardness table for a Bosch dishwasher.

Important! Combined tablets with hard water will not replace salt, since water passes through an ion exchanger, in the absence of salt it will simply fail, you will have to turn in the car for repair.

Another way to soften the water for a dishwasher is to install a filter, such as a polyphosphate filter, on the water supply. The main thing is not to forget to clean it in time. Otherwise, at one point, the machine will give error codes and stop washing.

Thus, determining the hardness of the water at home is not difficult. Do not neglect this, it will help you protect the dishwasher from breakage, as well as optimize the consumption of salt. In addition, you will probably notice changes in the quality of washing dishes, streaks and plaque will disappear.