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6.4 System- and servicing indications
LED shining “green” continuously
Operation
Humidification is demanded. The humidifier operates automatically. Without demand of humidity the LED remains
dark.
red flash in the shining “green”
Niveau max. attained
Occurs when the Niveau max. sensor is activated. This causes a momentary closure of the inlet valve.
LED blinking “red-green-red-green”
Manual drainage open
Manual drainage is activated, the drainage-button has been pressed.
LED blinking “green”
Cylinder service “U1”
The steam cylinder can no longer attain the nominal output and needs to be cleaned or perhaps replaced (refer to
chapter 7.3). This is purely a servicing code, the unit does not switch off automatically. The humidifier continues to
function at a reduced output.
LED shining “red” continuously
Excess current “U2”
Whenever there is excess current (140 % of nominal value) the humidifier switches itself off for safety reasons.
After the fault has been rectified, the humidifier is put back into operation by pressing the main power switch.
LED blinking “red”
Continuous fill “U3”
The humidifier tries to fill the cylinder continuously. Either a heating phase or the water is missing. The humidifier
switches itself off automatically after 30 minutes. After the fault has been rectified, the unit is put back into
operation by pressing the main power switch.
LED blinking “red-red-green-green”
Microcontroller uncoded “U4”
This signal appears if a replacement electronic control unit has been fitted to the humidifier without being coded.
The humidifier is prevented from operating. The signal disappears as soon as the controls unit has been coded.
6.6 Remote indication
A standard, potential-free relay output enables the alarm messages to be remotely displayed.
6.7 Safety functions
NORDMANN humidifiers are protected against running dry, i.e. the power is cut off automatically as soon as the
electrodes in the steam cylinder protrude above the water level.
If current consumption becomes excessive (25 % above the nominal level), the outlet valve is opened automatically.
Because the electrodes are then in contact with less water, current consumption falls back to the nominal value.
If the current fails to fall below 140 % of the nominal level even after several drainage operations, the humidifier
turns itself off automatically and the failure message “U2” (continuously red) appears on the LED display.
