Decalcify the heat exchanger - what to look for

Like all devices, heat exchangers can also be descaled. However, you have to pay more attention to heat exchangers than with other devices. How it works, how to best go about it, and what decalcifiers are right is explained here.

Preparations for descale

The device must first be disconnected from the mains. After that it has to cool down. Only then you can remove the hoses at the inlet and outlet of the heat exchanger.

Next, a suitable water tank must be procured, which corresponds to the amount of water in the heat exchanger.

by pumping

The descaling solution comes into the water tank in which the heat exchanger is located. In most cases these are formic acid with additional metal protection, but occasionally descalers with other acids are also available. Follow exactly the instructions for use.

The descaling is designed so that an (acid-proof!) Pump, either as a submersible pump or as a suction pump, draws in the descaling solution and feeds it via a hose into the inlet of the heat exchanger.

Another hose, which is attached to the outlet of the heat exchanger, leads the used solution back into the vessel. A permanent flow is important, otherwise the lime dissolved by the acid would not be removed from the heat exchanger.

During the procedure, a pH test strip should always be used to check that the acid has changed its pH. If it is no longer acidic (pH significantly less than 7), it will not dissolve lime. It then has to be replaced by a new solution. Thereafter, the process is continued until no more bubbles form.

Safety measures

As always when handling acids and alkalis, appropriate care is required. Gloves protect against acid damage on the skin, the clothing should be as long-lasting as possible and insensitive to acid splashes.

If possible, you should protect your eyes with goggles during the procedure - acid splashes into the eye are not only painful, but also dangerous.

Tips & Tricks

As soon as no bubbles form in the descaling solution, either the acid is no longer acidic, or the heat exchanger is completely cleaned.

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