Ygnis VARJET Serie Manual Tecnico página 78

To optimise how the equipment operates, plan to remove its calcium deposits. This must be done by a
specialized company. Also, before putting the unit into service, verify that the heating system is not damaged (ex.
leaks). If it has excessive scaling, the unit's settings for operation and for water treatment must be adjusted.
Protecting steel and stainless steel boilers against corrosion
Corrosion can affect the iron components used in boilers and heating systems, which is directly related to the
presence of oxygen in the water heater's water. Dissolved oxygen that enters the unit when it is being filled for
the first time reacts with the equipment materials and quickly disappears. Without refreshing the oxygen through
significant contributions of water, the unit might not experience any damage whatsoever.
However, it is important to follow the sizing rules and installation guidelines in order to prevent oxygen from
continuously flowing into the heating water. From these rules, we have:

Preferably an expansion vessel with a membrane rather than an open expansion vessel that allows
direct passage

Internal pressure with the unit of more than 1 bar cold

Remove leaky (permeable) components that are letting out more gas than as if they were sealed.
If the guidelines above are followed, the unit's system water has the proper characteristics to last a long time:
8.2 < pH < 9.5 with a water concentration of < 0.1 mg/l.
If there is a chance that oxygen could enter the unit, you must take additional precautions. Adding an oxygen
scavenger (ex. sodium sulphite) is highly recommended. We recommend directing any water treatment questions
to specialists, which can provide:
- The appropriate treatment based on the characteristics of the unit
- A monitoring agreement with a guarantee as to the results
For units in which the water comes into contact with heterogeneous materials, such as copper or aluminium,
appropriate treatment is recommended in order to ensure that the unit will last. In most cases, this consists of
adding corrosion inhibitors (in the form of chemical solutions) to the unit. Referring to a water treatment specialist
is recommended.
Unit monitoring
If the recommendations listed above (new installation or renovation) have been followed, the unit monitoring is
limited to:
- Checking the amount of make-up water (fill water volume + make-up water volume < 3 times the
unit volume)
- Checking the pH level (stable or slightly increasing)
- Checking the total hardness (stable or slightly decreasing)
We recommend monitoring these parameters two to three times a year. Note: Monitoring the quantity of make-up
water is critical to the long life of the unit.
If any of these parameters deviates from the above recommendations, refer to a water treatment specialist to
correct the problem.
Setting up a plate exchanger
If the recommendations listed above cannot be met, you can set up a plate exchanger to separate the primary
system from the secondary system, which protects the boiler from undesirable effects.
Setting up a filtration system
A filtration system on the back of the boiler is recommended in order to remove suspended particles from the
unit.
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