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Does Your Cistern Fill Valve Save You Money?


  • Toilet
  • toilet repair
  • water
  • water saving

The majority of people are familiar with the water saving capabilities of a dual flush toilet cistern valve. But, did you know, every time your cistern’s fill valve is activated, you could be saving significant amounts of water, and money for those on a water metre? Read on to find out more…

There are two main functioning parts inside a toilet cistern: the toilet flush valve, which enables water to flow into the bowl during the flush and the fill valve, which facilitates the refill of the cistern.

What you may not know is that traditionally, both of these functional valves will be triggered when the toilet flush is activated. So, as the water begins to rush into the pan when the flush is activated by the user. Simultaneously, the fill valve will start to fill the cistern with fresh water. Naturally, as these two functions start to happen at the same time, a portion of the water which is passing into the tank as part of the refill, is immediately expelled into the pan whilst the toilet flush is active. Once the flush valve closes, the fill valve continues to feed water into the cistern until it reaches the marked water line. On average, a fill valve that activates when the flush begins could waste up to approximately 1 litre of water per flush. 

The team at Fluidmaster UK was keen to address this water wastage happening during the fill cycle. They recognised the need for an intelligent fill valve, which allowed for significant water saving. At the same time, the team wanted to create a product that would tackle the issue of cistern backflow, a problem which can happen if the cistern isn’t set up correctly. So began work on the creation of the AirGap 6000 toilet cistern fill valve.   

According to Severn Trent Water: “Toilets are the second highest domestic water-using device after showers. They account for one-fifth (22%) of the average British household’s water consumption. In a year, the average household flushes the toilet about 4,600 times. That’s about 28,000 litres of water – enough to fill 350 standard baths.”

Designed and manufactured in the UK, the team designed the AirGap 6000 water saving fill valve. This unique toilet fill valve saves water by ensuring that the cistern doesn’t start to refill until the flush function has completely finished. By momentarily ‘delaying’ the cistern refill, approximately 1L of water can be saved per flush. 

This mechanism still flushes the correct amount of water to ensure cistern functionality and effectiveness. In independent testing Fluidmaster’s revolutionary AirGap 6000 technology was shown to save 21% to 31% water per use, compared with a competitor valve.

The AirGap 6000 is compliant with UK Water Fittings Regulations. To ensure compatibility, designers engineered the AirGap 6000 to fit virtually all cisterns. Available in both side and bottom entry; quick and simple adjustment options ensure that the height can be altered to suit virtually all cisterns on the UK market. The AirGap 6000 fill valve is also the only available adjustable solution which contains high-performance features whilst complying with BS1212-4 and all required water regulations. 

Explained Stuart Cronie, Sales Director, “The AirGap 6000 is ideal for specification, maintenance or repair of toilets in homes and washrooms. It ensures ongoing compliance and protection of toilet systems, whilst enabling significant water and Co2 savings with every flush.”

With an average of four people in each household in the UK, each flushing the toilet cistern five times a day, the amount of water expended through toilet use is significant! Considering that the use of toilet systems in commercial buildings is substantially higher, it’s easy to see why significant water conservation can be made by installing more efficient, water saving fill valves.

When paired with a high quality dual flush valve, the AirGap 6000 can transform your cistern into the most efficient option for flushing and filling your toilet. 

Other features of the AirGap 6000 include: 

  • Brass shank prevents cross threading
  • Side or bottom entry
  • Water saving fill valve – saves up to 1 litre with every flush
  • Fits virtually all cisterns
  • Spiral vortex generator for quiet cistern refill
  • Airgap technology – prevents back siphonage and with no need for an additional check valve.
  • Installation can contribute to BREEAM points
  • Full recyclable