Control settings

Temperature selection (Supply air / Extract air / Cooling)

The supply air temperature control method defines how the ventilation unit controls the temperature of inflowing air. The control method determines how the unit reacts to changes in indoor and outdoor air temperature. The temperature setting (+5…+25°C, recommendation: +18°C) is set in the ventilation mode (At Home, Away, Boost, Custom) settings.

• Supply air (factory setting) — The supply air temperature is maintained at the set target value (+5…+25°C). The unit uses automatic heat recovery and, if necessary, post-heating to maintain the target temperature.

• Extract air — The supply air temperature is adjusted automatically according to the temperature of air extracted from indoors. The unit reacts to changes in indoor air temperature and maintains balanced indoor air conditions. If the apartment is warm, the supply air is cooled down automatically and vice versa.

• Cooling — This control method is based on the extract air temperature. In addition, ventilation is boosted when necessary to keep the supply air temperature close to the target temperature, especially in warm weather. This control method is ideal for situations, in which the indoor temperature rises easily.

Humidity control (Automatic / Manual)

The humidity control method determines how the ventilation unit reacts to the humidity level of indoor air. The unit’s integrated humidity sensor is located in the extract air chamber. The unit can also be connected to an external humidity sensor (optional) installed in the apartment.

The humidity control boosts the fan speed to the speed set for the Boost mode. If the Boost mode is activated, the speed can be increased to the maximum fan speed. In any case, the humidity control does not reduce the fan speed below the level set for the active ventilation mode (e.g. At Home, Away). The humidity control can be disabled from the ventilation mode settings.

Adjustment options:

• Automatic (factory setting) — The automatic mode is suitable for regular household ventilation. The ventilation unit determines the normal humidity level automatically and updates it seasonally. The ventilation unit strives to restore the normal humidity level after a shower or cooking, for example. When the unit is started up for the first time, it takes approximately 3–10 hours for the unit to determine the humidity level. During this time, the humidity level cannot be adjusted and the screen says Calibrating. When automatic adjustment is enabled, the humidity limit is not set separately.

  

• Manual — The manual mode is ideal for spaces, in which the humidity level of indoor air stays constant around the year, for example in indoor pool facilities. The humidity level is set between 1 and 99%RH, and the ventilation unit strives to maintain this level. When manual adjustment is used, the humidity limit must be set separately (see Setting the humidity limit).

Humidity limit

• When the humidity control is set to Automatic, the unit determines the base level automatically. This mode is ideal for regular household ventilation, and the user does not have to set the humidity level separately. If the screen says Calibrating, the unit is in the middle of determining the normal humidity level.

• When the humidity control is set to Manual, the user must set the humidity limit between 1 and 99%RH. Usually, the suitable humidity level for a normal living environment is around 40–60%RH. A higher humidity limit (e.g. over 70%RH) is suitable for spaces with a naturally high humidity level, such as indoor pool facilities or humid work environments.

CO2 limit

The ventilation unit adjusts the fan speed automatically according to the carbon dioxide content of indoor air. The carbon dioxide level can be set between 500 and 2000 ppm, and the factory setting is 800 ppm. This level is suitable for regular household use and ensures a good indoor air quality.

You can set the level higher if, for example, there is a large number of people in the apartment simultaneously and ventilation seems to activate too easily. A lower carbon dioxide level improves the indoor air quality further, as the system reacts quickly to minor increases in carbon dioxide content and activates the ventilation.

The ventilation unit is equipped with a carbon dioxide sensor, which is located in the unit’s extract air chamber. A separate carbon dioxide sensor (optional) can also be installed in the apartment. The carbon dioxide control boosts the fan speed to the speed set for the Boost mode. If the Boost mode is activated, the speed can be increased to the maximum fan speed. In any case, the carbon dioxide control does not reduce the fan speed below the level set for the active ventilation mode (e.g. At Home, Away).

Constant airflow limit

By default, the constant air flow limiter is deactivated. When the function is activated, it monitors the ventilation unit’s operation automatically, and the unit runs as usual with the constant air flow function enabled. If ventilation performance becomes weaker due to, for example, a blocked filter, the constant air flow limiter stops the fan speed from spiking to avoid excessive noise. The limiter icon indicates when the function is active.

When the air flow returns to normal (e.g. after the blocked filter has been cleaned), the constant air flow limiter is deactivated automatically and the unit continues to adjust the constant air flow normally. The function remains in stand-by mode. The function is used in locations, where the filters are replaced centrally, for example, in apartment blocks.