Safety shutdown
Supply air temperatures too low
If the supply air temperature falls to 5 °C, the ventilation unit shuts down completely for reasons of safety. The fault message Error group 4 is displayed on the operating unit, the LED flashes.
If the supply air temperature again increases to at least 10 °C, the ventilation unit starts up automatically.
Exhaust air temperatures too low
If the exhaust air temperature falls below 12 °C, the ventilation unit shuts down to prevent rapid, unwanted cooling of the building. If this happens, there is a malfunction in the external heating system (Error group 4).