An arrangement that is as simple as possible and that has very few lines, has a valve with a base element having a regeneration nozzle in which a regeneration channel is formed, having an outflow nozzle in which an outflow channel is formed, and having a drive flow nozzle in which a Venturi tube is accommodated, whereby the regeneration channel, the outflow channel and the Venturi tube are flow-connected is characterized in that a closeable bypass channel is provided which opens up into the drive flow nozzle and which is configured there in such a way that a fluid that is flowing in through the regeneration channel can be discharged through the Venturi tube as well as through the bypass channel.