How does it work?
Propelair is an entirely new type of technology using displaced air and water. The simplicity of combining these two elements produces a high-performance flush which only requires 1.5 litres of water.
See how it works
How Propelair differs from other technologies
Water flows from the cistern into the pan under gravity, carrying the waste out into the drain. As water volume reduces, so does available performance. Water regulations require all new WCs to have a maximum cistern capacity of 6 litres.
Instead of flushing with water flow and gravity, waste is shredded into slurry and electrically pumped through small-bore pipes to meet the main drain. Can be noisy and prone to blocking the shredder.
Dual-flush: This uses the same flushing principle as standard WCs. Dual-flush cisterns are permitted if the method of operation is clear and the lesser flush is no more than two-thirds of the full flush.
Low-flush: Several companies now offer WCs with flush volumes of three litres, but they are based on existing technology and suffer from the same poor performance and contamination problems as dual-flush WCs.
These systems improve performance by using the pressure of the incoming refill water to compress an air store, which acts upon the next flush to boost water flow into the pan.
Requires the building to be fitted with a central vacuum drainage system which sucks waste out of toilets during flushing for onward disposal. They require little water to flush due to the power of the vacuum, but are energy intensive and cannot connect to existing drains.
When the toilet is flushed, a trap door opens to allow the waste to drop into a second compartment, which a compressed airline is able to pressurise to force the contents through a small bore waste pipe.