Dimensions and duct outlets Figure 1. Dimensions with the cooker hood 1 Extract air fan 2 Supply air fan 3 Fine filter for supply air 4 Heat recovery cell 5 Bypass damper for the HR cell 6 Coarse filter for supply air 7 Coarse filter for extract air 8 Post-heating resistor 9 Safety switch Figure 2. Duct outlets, R model Inner diameter of the female collar ∅ 125 mm. 1 Supply air from the unit to the apartment 2 Extract air from the apartment to the unit 3 Outdoor air to the unit 4 Exhaust air flowing outdoors from the unit Figure 3. Duct outlets, L model