Water Watch - Electronic Urinal Flush Control Systems

Operation of the Water Watch Urinal Flush Control System

Operation of the Syphonic Urinal Cistern

Virtually all WC urinals in the UK operate using an automatic syphonic cistern. The cistern is supplied with a continuous flow of water. When the level of water gets to a fixed level in the cistern, syphonic action starts and all the water held in the cistern is flushed to the urinals. This flush cycle repeats continuously 24 hours a day. The number of flushes per hour is set by the flow rate of water to the cistern.

Water Watch Overview

The Water Watch intelligent flush control system comprises of a simple retrofit kit that can be installed to existing urinal toilets in 30 - 40 minutes or can be used in the construction of new urinal facilities conforming to the latest Water Bye Laws .

The Water Watch system consists of a water control valve fitted to the water inlet pipe prior to the petcock. This valve is electrically operated by the Water Watch sensor. The sensor detects individuals using the urinals using a PIR (Passive Infra Red) detector.

The Flush Cycle

Consider the first flush cycle of the day.

On first detecting occupancy within the detection zone an internal timer is started. This timer sets the delay between use of the toilet facility and the flush commencing. One of four time delays can be selected; 15, 20, 30 or 60 minutes. The Water Watch is normally installed with a default delay of 20 minutes. At some point during this delay period the water control valve will be opened to start filling of the cistern. The valve will be opened early enough so that when the timer has finished the cistern will have been filled from an initial empty state and so a flush will commence. The valve will then be closed.

Water Watch Flush Cycle

The cistern fill time is the time for which the valve is open during a flush cycle and is set when commissioning the control.

When a flush cycle has finished the Water Watch sensor is immediately ready to commence a new flush cycle on detection of the next occupancy within the detection zone.

Because the sensor relies on detection of use, there will be extended periods when no flushing is required. For example no flushing is required during evenings, weekends and holidays. Water Watch will do a single hygiene flush after 24 hours has elapsed without detecting occupancy.

Extensive documented research has shown that savings in water consumption between 50 -95% are achieved while maintaining a rate of 3 flushes per hour during normal working hours of use.

Commissioning Switch Moving switch to open position opens the valve and allows water to flow into the cistern. Closing the switch when the cistern is full and begins tto flush shuts the valve. The time taken is logged by the control and set for all future operations.     Operating Sequence Repositioning the links on the 3 switches alters the delay settings. Flushing can be set to commence 15, 20, 30 or 60 minutes following the detection of a person entering the washroom.