Save Water With A Toilet Cistern Saver Siphon

John Adams
Tuesday, 10th May 2011

John Adams reviews an ingenious water saving product that saves up to half daily flush usage (typical saving 30 litres a day), a nearly 50% improvement on average duel flush system. Can cut water bills by 20-40%. Trap door design, no diaphragm to replace. Fits all WCs with a pipe between cistern and pan.

Here in the UK, even in the wettest winter we are reminded that water levels are not as they should be and if there is a dry summer water may be rationed. On top of which, if your water isn't already metered it probably will be soon, so anything that reduces the amount of water we waste is a good idea. One water saving device that really stands out is the Interflush Saver-Siphon. This is an ingenious reinvention of the siphonic cistern valve which the makers claim can save as much as 30 litres per day, about half the amount we normally flush away daily. That's around 11,000 litres (2,400 gallons) a year!

It replaces almost any standard sized cistern siphon unit on toilets which have a pipe connection between the cistern and the pan, as long as it is handle or chain flushed. The Saver-Siphon is well made and has a mechanical trap door instead of a membrane diaphragm, so has nothing to wear out as in traditional designs.

I tried this out on our downstairs toilet which is fairly ancient and not a standard size either. It has only recently had its innards replaced which was when I discovered that really it needed a special short siphon unit. As such a thing wasn't available I had to modify the handle to plunger connection to make a standard one work. So it was with some trepidation that I took this carefully modified unit out and replaced it with the Saver-Siphon. It was actually very easy. First I turned off the water and flushed the cistern, then mopped out the remaining water. Then I detached the handle and removed the two plastic pipe nuts under the cistern and lifted out the siphon unit. The Saver-Siphon went in and with a bit of Plumbers Mate round the bottom seal, the fittings were reconnected. The water went back on and the toilet was working again in under 15 minutes. It takes a little getting used to but it really works very well once you remember to hold the handle down for the required time rather than flushing and walking away.

So far my family seem quite impressed. As my daughter said, " It seems odd not to hear the whole cistern flushing away, but you quickly realise how little water you really need to use". Much cheaper and more reliable than changing to a valve multi-flush. Fit one, and start saving bucket loads every day! 

The item reviewed here is available to purchase from