The flush valve, as the name suggests, is a component installed in the toilet cistern to flush the contents of the toilet through the drain into the sewer/septic system. Next let's understand how the flush valve works.

The toilet flush valve is located in the center of the cistern and is a plastic or brass fitting. It is operated by a rubber or neoprene flap or "float", a device in the toilet that rests against the valve opening and keeps water in the cistern (until the flush handle is operated). When the handle is depressed, a chain or lift wire attached to the handle rod lifts the flapper from the seat, allowing water to flush out of the cistern and fill the toilet. When the cistern is empty, the flapper will drop back into the valve seat, sealing the opening and allowing water to refill the cistern. Integrated with the flush valve is a vertical overflow line that extends from the bottom of the flush valve up into the cistern. The purpose of this overflow tube is to prevent water from overflowing the cistern, but also to allow a small amount of water to flow in and fill the toilet when the cistern is refilled. A small make-up tube on top of the overflow tube allows water to flow down into the bowl during the make-up cycle. This restores the level of standing water in the toilet and keeps the trap sealed.

If you have questions about toilet flushing systems or are interested in our cistern series products, please contact us.