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10. Operating level 2
Humidification
Isothermal and adiabatic humidity systems can be used.
Supply air humidity control
A constant level of supply air humidity will be maintained.
For systems with variable supply air temperature (indoor / extract air / supply air
cascade), the absolute humidity will be defaulted as a set value.
The value resulting from the required relative humidity at the required room
temperature is entered as the set value for absolute humidity. For example, if the
supply air temperature must be reduced because of insolation, the relative humidity
will, nevertheless, remain constant. The same applies if the supply air temperature
reaches 40 °C, for example.
At a constant supply air temperature (supply air temperature control), a set value for
absolute or relative humidity can be entered.
Supply air control is always appropriate if no representative room humidity level can
be captured, e.g. if several rooms are supplied together.
Room humidity control (extract air humidity control)
A constant relative humidity will be maintained, without exceeding the maximum
supply air humidity.
A set value for the absolute supply air humidity is calculated from the deviation
between the set and the actual room humidity. The greater the deviation, the greater
the change of the set supply air humidity.
Control of the room humidity relative to the actual room temperature:
The set value for the absolute supply air humidity is calculated from the deviation
between the set and actual relative humidity and the actual room temperature. As
a result, the relative room humidity remains constant, even when the actual room
temperature changes.
This is important for processes that demand a constant relative humidity.
Control of the room humidity relative to the set room temperature:
The set value for the absolute supply air humidity is calculated from the deviation
between the set and actual relative humidity and the set room temperature. The
relative humidity drops, if the room temperature rises above the set value, however
the absolute room humidity remains the same. This prevents the air from being
humidified when temperatures are high. In occupied rooms, a lower room humidity at
high temperatures is often perceived to be more pleasant.
Priority for temperature control with adiabatic humidifiers:
The humidification level is reduced after expiry of an adjustable interval if the
operation of the humidifier precludes the set supply air temperature from being
achieved. Sizing the humidifier for cold (dry) outdoor air with a high outdoor air
proportion can result in controllability problems at higher outside temperatures. The
option is therefore provided to enable the control only up to an adjustable outside
temperature. The system runs on for an adjustable time to dry it out if it shuts down
whilst the humidifier is active.
Standard mask
Esc
Main menu
Contractor
Humidity control
Hygrostat function
A room or duct hygrostat switches when a specific humidity level is exceeded. When
the contact is closed, the following actions will be performed:
When the system is operational, the fresh air proportion and the speed or stage
of the fan are increased to a selected value. Only the speed will be increased on
systems without mixer air damper.
When the system is switched off, it will be activated with the selected values when
the automatic sequence is activated. In that case, the set value programmed for
manual mode will be used as set temperature.
Continuous hygrostat function
The continuous hygrostat function can be enabled in the standard settings. Via a
moisture sensor, the relative humidity of the room or the extract air is captured.
When the relative humidity in the room or extract air rises, the fan speed increases
or switches to a higher stage and the fresh air proportion increases by opening the
outside and discharge air damper (if installed). In single stage fans or in the case of
pressure or flow rate control, only the fresh air proportion is increased. If the system
is switched off, it starts when the "Humidity start" limit is exceeded.
Please note The hygrostat function takes priority when combined with an external
stage demand.
10.2.16 Humidity control
Humidity control
DISPLAY
SELECTION
Esc BACK
Prop. fresh air for
hygrostat function
100 %
F-01
