Prevent calcification & decalcify your high-pressure cleaner correctly

EXPERT KNOWLEDGE HIGH-PRESSURE EXPERTISE

Limescale deposits accumulate in the pipes of your high-pressure cleaner when water with a high magnesium or calcium content flows slowly or rests in hot pipes. Calcification problems occur regionally where “hard” water (for example from mountain springs) is used in th, sh or Dynabox series DYNAJET hot-water machines.

Determining water hardness

Soft water contains less than 1.5 millimoles of calcium carbonate per litre of water. This corresponds to less than 8.4°dH (German hardness). Hard water is when there is more than 2.5 millimoles of calcium carbonate per litre (more than 14°dH). Your local water supplier will be able to tell you the degree of hardness of your water. Alternatively, you can analyse the water yourself or have it done by a laboratory.


DYNAJET prescribes a hardness level of 3-25°dH for high-pressure cleaners up to 350 bar. For cleaners from 500-1200 bar, 3-20°dH are permitted and above 1,200 bar the maximum value is 15°dH. You can find these values in each DYNAJET high pressure cleaner’s operating instructions in the “Water quality requirements” section.

Prevent calcification in your high-pressure cleaner

  1. Always cool the burner down

    Before shutting down a hot-water machine, always allow the burners to cool down while water is still flowing through them. To do this, switch off the burner after completing the cleaning work and keep the gun activated, with the machine still running, until the thermostat display shows that the system has cooled down considerably to a water temperature of below 50°C.

  2. Detect limescale in good time
    Find out if the high-pressure lines are calcified by disassembling the gun and starting the machine in cold mode with the burners switched off. Select a high speed. The pressure gauge will now show you any pressure loss of your piping system. If this pressure loss exceeds 50 bar, it is time to decalcify the machine.

  3. Have limescale protection installed
    DYNAJET offers limescale protection which reduces the build-up of limescale within certain limits. Its galvanic element constantly releases small quantities of zinc ions. As a result, the limescale does not flocculate, but forms tiny particles that do not stick because of the flow through the piping system. The system provides noticeable improvement, although not complete protection where the water is extremely hard.

Correctly descaling the burner spiral

Lime mainly affects the burner spiral. If you have detected limescale in the system and the pressure loss in your machine is already significantly over 50 bar, decalcifying the system is the only thing that will help. I the same way as descaling a coffee machine, the pressure washer gets rinsed with a descaling agent (usually vinegar or citric-acid based). This dissolves the lime. Your DYNAJET service partner will be happy to carry this out for you as part of routine machine maintenance.

It is important to make sure that the descaling agent only rinses the burner coil and does not come into contact with the sensitive machine sensors. Seals and non-ferrous metals can get damaged by the descaling agent.

Further information:

Equipped for every challenge – DYNAJET offers a comprehensive range of high-quality accessories for working with your high-pressure cleaner. DYNAJET accessories are compatible with almost all common professional high-pressure cleaners.