Cisterns

Before 1993, the cisterns for flushing the toilet were 9litre (2 gallon) capacity. In an effort to try and save some of this water, the volume was reduced, firstly to 7.5litres and then eventually to the amount that is still in use today of 6litres. The WC system works by using something called the “Siphonic valve”, but nowadays there is another design in which a valve will lift to allow water to flow. The WC cistern is different today than many years ago, and is now actually, quite a modern piece of technology. Worcester Boiler Repair London fit WCs.


The water supplied to the cistern was controlled by a float-operated valve, which would sit floating on top of the water level. This would then lower when flushed as the water left the cistern and by doing so would open the fill valve at the bottom allowing the cistern to fill once again. Once the float had lifted with the level of the incoming water it closed the inlet valve and stop.


Siphonic Action:

As water leaves a tank or cylinder without help of a mechanical nature it is said to have a siphonic action. It will travel up and over a tube shaped like an upside down ‘J’. The long leg joins to the flush pipe whilst the short leg is open to the water in the cistern. When the air inside is taken out, this will create a partial vacuum. This begin as a large diaphragm washer lifts and causes a volume of water to discharge away through the flush pipe taking air and causing a partial vacuum. Worcester Boiler Service


London know siphons.

Flush:

Two flush buttons are usually now fitted to a modern cistern, the first is designed to carry out a short flush (low volume of water) and the second is designed for a longer flush (larger volume of water). They use a two-rod system which releases the small and larger volumes of water as required.