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12.2 Other functions
12.2.1 Measurement of the conductivity of the supply water
The conductivity of the supply water can be measured. This is done when opening the fill electrovalve, using special elec-
trodes located in the tank. The range of reading is from 0 to 1500 µS/cm. Two thresholds are avai lable for this measure-
ment:
b5
: pre-alarm threshold (signal only, without activation of the alarm relay, automatic signal reset when the causes pass);
b6
: alarm threshold (total machine shut-down, activation of the alarm relay). The alarms are activated when the measure-
ment exceeds one of the two thresholds continuously for 60 minutes, or alternatively instantly if the measurement ex-
ceeds 3 times the threshold. To exclude one of these thresholds, simply set the corresponding value to a level outside
the range of reading of the conductivity meter, that is, above 1500 µS/cm.
12.2.2 Automatic draining
Automatic draining is managed by the controller: part of the water con tained in the cylinder is drained automatically, and
replaced with fresh water to prevent an excessive concentration of salts following the process of evaporation.
The drain electrovalve is opened for a set interval whenever the internal conductivity exceeds the maximum limit allowed;
this situation can also be seen indirectly by evaluating the speed of evaporation. During automatic draining, the electrodes
are not powered, so as to prevent the drained water from carrying electrical current (also see para graph 12.2.6). During this
phase, the display signals “AF”.
12.2.3 Anti-foam procedure
Some particular types of supply water may give rise to situations in which, during the production of steam, foam forms on
top of the water; this situation must be avoided as it may lead the release of droplets of water together with the steam. For
this purpose, the top of the cylinder is fitted with two detection electrodes. When these electrodes reveal the presence of
foam, a drain procedure is activated to eliminate this pro blem. The procedure consists of repeated draining up to, in more
critical situations, the automatic and complete cleaning of the cylinder.
12.2.4 Dehumidification request signal
If activated, this function closes the contact of a relay when the relative humidity measured by the transducer connected
to the controller exceeds the set threshold. This signal can be used to start an external dehumidification device (also see
paragraphs 2.2.3 and 2.2.4).
12.2.5 Automatic emptying of the cylinder for extended shut-down
If the humidifier remains on but is not actively producing for a number of days equal the value set for the parameter “bF”
(default 3 days), the water contained inside the cylinder is completely drained. This function prevents the corrosion of the
electrodes by strongly saline water in the case where the humidifier is off for extended periods. Refer to par. 8.3, in particu-
lar parameter b1 of the special functions, during this drain phase the display shows the code “idr”.
12.2.6 Powered draining
When automatic draining is performed to discharge the accumulated salts (also see par. 12.2.2), the electrodes are not
powered. This creates a temporary reduction in steam production. If, vice-versa, the electrodes should remain powered in
this phase too, “powered draining” can be enabled.
Refer to par. 8.3, in particular parameter b1 of the special functions.
12.2.7 Draining due to a significant reduction in the request for pro duction
In the event of a significant reduction in the request for steam production, the humidifier, rather than wait for the level of wa-
ter (and thus the production) to decrease due to the effect of the production itself, drains some of the water. The reduction
in the request for steam production is considered significant if the current is 33% higher than that relating to the requested
level. This function can be disabled. Refer to par. 8.3, in particular parameter b1 of the special functions.
12.2.8 Disabling the “cylinder being depleted” and “cylinder depleted” alarms
The “cylinder being depleted” and “cylinder depleted” alarms are both present. The two alarms can be enabled/disabled as
follows:
Set parameter b1: if b1 < 16, the two messages are already disabled; if b1
≥
16, decrease the value by 16 to disable both
the messages. Example: b1=8 fi the messages are already disabled; b1=18: the messages are enabled fi decrease b1 from
18 to 2 (=18-16) to disable both the messages (see par. 8.3).
N.B.: the alarms are enabled/disabled together, they cannot be enabled/disabled separately.
12.2.9 Complete periodical draining (H controllers)
With certain types of water the cylinder needs to be periodically drained (water with impurities, humus, very aggressive
water). To activate the periodical draining function, the weight 64 must be set for parameter b1. At this point, as default
every 24 hours the controller will run a com plete drain cycle of the cylinder, and the display will show the code “dP” (periodi-
cal drain). If periodical draining is enabled, the number of hours between two drain cycles can be changed, by setting the
parameter “bE”.
