Cylinder Service Life - Carel compactSteam Mode D'emploi

1.1 Cylinder service life

Basic information
The plastic cylinder containing the electrodes is the most
important component of the humidifier. During operation,
the water in the cylinder boils to produce steam. As the steam
does not entrain any of the minerals dissolved in the water, the
concentration of such minerals will increase the more steam
is produced; moreover, some salts (especially calcium and
magnesium bicarbonates) tend to foul the electrodes, until
these become electrically insulated. As the electrodes become
progressively coated with scale, the water level in the cylinder is 100%
20%
Maximum production
increased so that a new portion of clean electrodes can conduct
the current. Eventually, the electrodes will be completely coated
with scale and will no longer be able to conduct the current
needed to produce steam. The humidifier controller can detect
when there is low current between the electrodes, indicating the
end of the cylinder's service life; this is displayed by alarm code E3.
Fig. 1.c
Several factors influence cylinder service life (water characteristics,
such as hardness and quality, % of steam production); for the part
numbers specified in Table 8.a, the cylinder has a service life of
600 or more hours.
Cylinder service life and water characteristics
The characteristics of the water, which vary greatly depending on
the location, profoundly affect the cylinder's service life. The most
important characteristics are the amount of minerals dissolved in
the water and their chemical composition. For example, a high
calcium and magnesium bicarbonate content will cause fouling
that leads to a rapid reduction in cylinder service life. On the
other hand, a considerable chloride content in the water may
cause corrosion, with possible electrical discharges between the
electrodes.
Cylinder service life and humidity load
The demand for humidity influences the cylinder's service life. In
normal systems, where the humidity load is correctly estimated,
the humidifier will operate at maximum capacity only for brief,
intermittent periods. In this way, the water level inside the
cylinder increases simply to make up for the build-up of scale, and
this helps maximize the cylinder's service life.
In some special installations where maximum steam production
is required at all times, cylinder service life is reduced, as the
water level is generally higher and therefore scale builds up more
quickly on the electrodes. It is therefore extremely important to
correctly estimate the capacity of the humidifier in relation to the
required humidity load.
Cylinder service life and maximum production
Another factor that influences cylinder service life is the maximum
steam production that can be set on the unit. The higher the
steam production, the shorter the cylinder life, and vice-versa.
Figure 1.c qualitatively shows the ratio between maximum steam
production and cylinder service life.
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"compactsteam" +03U0092EF - rel. 1.0 - 2020.08.31