Water treatment system with backwashable precise prefilter unit

A water treatment system comprising:

• a backwashable prefilter column installation;
• and
• a five-channel ball valve having an original water inlet, an original water outlet, a filtered water inlet, a filtered water outlet, and a discharging channel, wherein the five-channel ball valve is switchable between the following working positions:
• a cleaning water position, a discharging water position, and a backwashing position,
• wherein an inlet of the backwashable prefilter column installation is connected with the original water outlet of the five-channel ball valve,
• wherein an outlet of the backwashable prefilter column installation is connected with the filtered water inlet of the five-channel ball valve,
• wherein the original water inlet of the five-channel ball valve includes a connector element for connecting with an outlet of a water supply, and
• wherein, by switching the five-channel ball valve to the different working positions, water passes through the water treatment system in three different manners as follows:
• when at the cleaning water position, incoming water passes through the inlet of the backwashable prefilter column installation, then through the backwashable prefilter column installation in a forward direction, then through the outlet of the backwashable prefilter column installation, and then through the filtered water outlet of the five-channel ball valve;
• when at the backwashing position, incoming water passes through the outlet of the backwashable prefilter column installation, then through the backwashable prefilter column installation in a backward direction, then through the inlet of the backwashable prefilter column installation and then through the discharging channel of the five-channel ball valve;
• and
• when at the discharging position, the incoming water passes through the inlet of the backwashable prefilter column installation, then through the backwashable prefilter column installation in the forward direction, then through the outlet of the backwashable prefilter column installation, and then through the discharging channel of the five-channel ball valve.