41
01/13424999894
Features
Indoor air sensors
General guidance
Automatic aeration and ventilation via indoor environment sensors is only possible in automatic operating mode (see
page 11, item 5 Connecting a manual/automatic selector switch). The flaps open independently of clock time. An optional
timer switch is recommended to prevent automatic opening at the wrong times (page 11, item 4 Connecting a wind and
rain detector and/or timer switch). A wind or rain signal takes precedence over an automatic control command.
Opening and closing via separate temperature sensors
(see page 12, item 7.1)
This type of connection allows the setting of a switching hysteresis (switching threshold) for the switch from OPEN to
CLOSED or vice versa. To set the desired switching threshold the two temperature sensors should be set to different
temperatures. For example, setting Sensor 1 to open at 20 °C and Sensor 2 to close at 18 °C results in a switching
hysteresis of approx. 2 °C. The advantage of this operation type is to prevent rapid switching, i.e. fast, uncontrolled
opening and closing of the windows every time there is a change of air conditions.
Opening and closing via one temperature sensor
(see page 12, item 7.2)
Automatic window opening and closing can also be controlled by connecting a temperature sensor. But it should be
noted that the switching hysteresis determines the sensor and cannot be altered. The normal hysteresis values are
0.5 °C, which can lead to uncontrolled opening and closing of the windows if the sensors are not carefully positioned. In
this situation the sensor should not be placed too near to air currents or draughts.
Opening and closing via a hygrostat / humidity sensor
(see page 12, item 7.3)
Since it is essentially ambient air humidity which determines comfort, automatic opening and closing of the windows can
be enabled by connecting a humidity sensor. The windows open or close automatically when the conditions drop below
or exceed the pre-set relative humidity (% F). It should be noted that, even when the outdoor temperature is cold, the
flaps will open automatically if the ambient air humidity is to high, and will only close automatically once conditions drop
below the pre-set relative humidity (% F). It is important to be aware of this so as to avoid damage to the building and its
furnishings (e.g. plants etc).
Combined ventilation via humidity and temperature sensor
(see page 12, item 7.4)
When control is via a combination of humidity and temperature it must be established which of these takes precedence.
In the example on page 12, item 7.4 the CLOSED temperature function takes precedence over control based on
humidity. This avoids the risk of damage to furnishings such as plants by preventing windows from being opened
because humidity is too high, even though the temperature is too low.
Ventilation control panel iVent 8A
