14
4.3 Putting the humidifier into operation
After the steam hose, water feed pipe, drainage pipes and electrical cables have all been correctly connected, the
AT 3000 humidifier can be switched on using the black power switch. When the T4 key is pressed, the LED for output
limitation lights up and the level of output limitation is shown on the display. All humidifiers are set ex works
to 100% output. If the SELECT key is pressed, you can choose a different level of output limitation.
As soon as the humidistat or humidity controller demands humidification, the green Humidification LED lights up,
the contactor is activated and, soon after, water is fed into the steam cylinder, whereupon fully automatic operation
commences.
Of course, the humidifier will operate automatically only if (a) it was installed by a specialist and (b) the shut-off valve
in the water feed pipe is open.
After the water in the steam cylinder has been heated up, the production of steam begins.
During the start-up phase, or after a new replacement cylinder has been fitted, the maximum water level, or Niveau
max. can be attained. When Niveau max. has been reached, the inlet valve closes briefly; this is a normal occurrence
during the steam cylinder’s concentration phase. The length of this phase can differ; it lasts until the cylinder has
reached the nominal rating. In the first stage of the service level, you can check whether Niveau max. has been attained
(see Item 5.6).
4.4 Automatic operation
The AT 3000 series’ special electronic controls unit with microcontroller regulates all operations automatically, so that
the user does not need to take any action or make any settings during normal running.
4.5 Programming level
The humidifiers of the AT 3000 series have a programming level which has a large array of functions, allowing
the unit’s characteristics to be matched to a wide variety of conditions or tailored exactly to the customer’s particular
requirements.
You are not permitted to use the programming level unless authorisation to do so has been granted by a NORDMANN
specialist. Your NORDMANN representative will be glad to advise you in this matter.
4.6 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 normal 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 current consumption fails to fall below 140% of the nominal level even after several drainage operations, the
humidifier soon turns itself off automatically, and «U2» appears in the display.
