Switching contact (potential-free)

Functions which can be switched with the potential-free contact on the main circuit board:

Alarm function: Switching contact open during operation. In the event of a fault, the contact remains closed until acknowledged.

Filter change function: The switching contact closes if a filter change is imminent.

Operating display function: If fans are switched to active (in ventilation level HPV, RV, NV or IV), the switching contact closes. The contact remains open when switching off or in the event of a fault.

With pre-heating/supplementary heating: Incorrect installation will result in unit damage. If external pre-heating or supplementary heating is selected, the power supply for the component should be switched via an external relay.

Supplementary heating function: The switching contact switches a downstream heat register on/off. The setting function of the supply air temperature is activated in the Temperature short code menu. The supplementary heat register’s supply voltage is led via an external relay and not via the contact on the basic circuit board.
Supplementary heating on: Switches on automatically when the temperature falls below the room setpoint temperature.
Supplementary heating off: Switches off automatically when the actual room temperature exceeds the room setpoint temperature. The actual room temperature is determined using the selected temperature sensor.

Pre-heating function: The switching contact switches an upstream external pre-heating unit (electric/hydraulic) on/off. The pre-heating keeps the unit free of frost.
Pre-heating on: Switches on automatically if the temperature falls below the minimum air inlet temperature (factory setting) + T air inlet offset heating.
Pre-heating off: Switches off automatically if the minimum air inlet temperature (factory setting) + T air inlet offset heating is exceeded.

Shutter function: The switching contact closes as soon as the fans switch on. If there is no speed, the contact opens. This also happens during pauses when operating with humidity protection.

Cooling function: The switching contact closes as soon as the max. room temperature has been exceeded.