08.04.2021
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CONDENSINOX -
Installation, Use and Maintenance
1.5.2. Protecting the unit against scaling
Water naturally contains dissolved calcium ions and carbonates that cause
scaling (calcium carbonate) to form. To prevent excessive deposits, take
precautions with regard to the water used to fill the unit:
hardness < 100 ppm
Water must be added during the life of the boiler. The new water adds scaling
to the water system. The amount of fill water plus the amount of make-up
water added during the life of the unit should not be more than three times
the water capacity of the heating system. Also, the hardness of the make-up
water must be controlled. Make-up water:
hardness < 50 ppm
Adding a large amount of untreated water always contributes a significant
amount of scaling. To monitor this and to detect problems, a system water
meter must be installed.
Failure to comply with these guidelines (such that the fill water plus the make-
up water is more than three times the water capacity of the heating system)
requires a full cleaning (to remove sludge and scaling) to be performed.
Additional precautions are required for operation:
- If a softener is present in the installation, the equipment must be
checked frequently to ensure it is not discharging chloride-rich water into
the system: the chloride concentration must always remain below
50 mg/litre.
- To prevent the build-up of calcium deposits (such as on exchange
surfaces), the unit should be brought into service slowly, starting by
operating at a low power with high primary water flow.
- If the water in the system does not have the required qualities (e.g.
high hardness), it must be treated. The fill water must be treated, and
whenever new water is added, the make-up water must also be treated.
- Installations with multiple boilers require all of the boilers to be brought
up simultaneously at minimal power. Doing this prevents the calcium in
the water from depositing on the exchange surfaces of the first boiler.
- When working on the unit, avoid draining it completely; only the required
parts of the system are to be drained.
The rules listed above are designed to minimise scaling on the exchange
surfaces and thus to increase the life of the boilers.
To optimise how the equipment operates, calcium deposits can be removed.
This must be done by a specialised company. Also, before putting the unit into
service, verify that the heating system is not damaged (e.g. leaks). If it has
excessive scaling, the unit's settings for operation and for water treatment
must be adjusted.
