Abstract: A painting system operating in recirculating air mode, comprising a spray booth (1) which has from the top downwards an air plenum (2), a painting zone (3) and a wash-out (4). The recirculating air flowing through the painting zone (3) picks up overspray particles which are largely removed again from the recirculating air in the wash-out (4) with the aid of a stream of water. The recirculating air passes through a conditioning unit (21) before said air is returned to the air plenum (2) of the painting booth (1). The conditioning unit (21) comprises at least one capacitor (29) and/or a droplet separator (30), with the aid of which a liquid can be recovered from the recirculated air. Said liquid is fed to a supply source (24, 25) for flushing liquid. The flushing liquid is used for cleaning the application equipment in the painting zone (3).