Measuring water hardness electronically - how does that work and does it make sense?

The water hardness in your own household plays a major role in the load of equipment by limescale and for the detergent and soap consumption. There are also devices for the electronic measurement of water hardness. Whether the use of such a device in the household
Makes sense, and what exactly measure these devices is explained here.

Information about the water hardness

In principle, the water suppliers are obliged to inform each household on demand about the water hardness in the respective area. Since the determination at the water supplier itself must be very precise, these values ​​are absolutely exact and reliable.

In some cases, stickers are also offered free of charge for the washing machine in order to be able to precisely dose the detergents used on the basis of the water hardness.

Determine water hardness with test strips

The total water hardness can also be determined very precisely with test strips. These strips give the values ​​in° dH and not in mg / l. This makes easier allocation to the individual hardness categories possible.

The values ​​that give test strips are in most cases very reliable. A determination of highly accurate values ​​is usually not useful for the household, and if so can be inquired at the water supplier here.

Measurements of electronic devices

Electronic hardness measuring instruments not only measure the total hardness of the water, but can also determine the calcium and magnesium hardness separately using the technology used (photoelectric measuring method).

This is often required in the industrial sector when it comes to cooling systems or piping in which corrosion is to be prevented. The ratio of calcium to magnesium ions also provides an important indication of water quality in the industrial sector. If the ratio of Ca to Mg (usually 4: 1) is greatly altered, this can be an indication of manure in the water.

For private use, the use of these devices makes no sense, since the values ​​are not needed. All relevant values ​​can easily be found at your own water supplier.

Tips & Tricks

Water softening should always take place above 14° dH, and the softening should be adjusted to give a water hardness of around 7° dH.

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