a liquid dispensing system for example for paints comprises a liquid reservoir , a circulating path for the liquid to and from the reservoir , a pump for causing a pressurized flow around the path , a three - way valve in the path which is controllable to divert liquid from the path via a second valve to a dispensing nozzle . the second valve is biased to a closed position and is openable by the hydraulic pressure of the diverted liquid to permit the diverted liquid to flow to the nozzle . in a multiple liquid dispensing system , e . g . a paint blending system , each liquid has its own dispensing system as described above and the plurality of second valves thus provided are disposed in a conical formation with the nozzles directed towards the apex of the cone .