Standard First Flush Device Kit
First-flush diverters are important to tank water quality. When it rains, water slowly builds up in the roof guttering system before it enters the downpipe. At this time the water is saturated with all the 'nasties'- dirt, pollens, bird droppings etc. To ensure the quality of water supply from a water tank, we want to prevent these 'nasties' from reaching the tank.
With a first-flush diverter fitted, as water enters the downpipe, it first flows into the diverter tube. As the water rises in the tube, so does a floating ball, until the ball seals off the tube. This seals the polluted water in the diverter tube. The rest of the roof water, minus most of the 'nasties', is then automatically diverted to the water tank.
When the rain stops, the diverter chamber empties itself through the control valve at around 1 LPH. so that the diverter tube is empty for the next time it rains.