Main parts

R model in the figure. In the L model, the parts are mirrored.

No.PartNo.Part
2aHeat recovery cell, 2 pcs6dPost-heating resistor (245 MV VKL)
3aExtract air fan7aSafety switch
3cSupply air fan9aCeiling bushing for electric wires
4aFine filter for supply air10aControl panel
4bCoarse filter for supply air11aInternal carbon dioxide and humidity sensor
4cCoarse filter for extract air11cCarbon dioxide sensor (optional)
5aBypass damper of the HR cell11dHumidity sensor (optional)
6aPost-heating liquid radiator  (245 MV)11eVOC sensor (optional)