The Tunze RO Water Controller 8555 is an automatic shut-off device used to control the water produced by a reverse osmosis (RO) unit.
It consists of the electronic controller with two float switches, a water control solenoid valve and a 11 volt power supply. One of the float switches can be located at the ‘high level’ of the RO storage tank and the other is put lower down in the tank as a power off. The water control solenoid valve is then plumbed into the mains water supply pipe connected to the RO unit. When the water in the RO storage tank reaches the ‘high level’ the float switch triggers the water control solenoid valve to switch off thus shutting off the mains water supply to the RO unit. If the water level in the RO storage tank then falls due to usage, such as evaporation top-off, then the RO will switch back on again to top up the storage tank again and keeping it the desired level.