Description3/4″ Spring non return valves these prevent the reverse siphoning of solar heating fluids after the sun goes down. Stopping the pipe work and on roof collectors from cooling. In addition to our 3/4″ Spring Non Return Valves that prevent the reverse siphoning of solar heating fluids, we also offer 1/2″ Spring Non Return Valves. Both valve sizes help to prevent on-roof collectors and pipe work from cooling down once the sun goes down, ensuring maximum efficiency of your solar heating system. Dragons Breath Solar Heating Components, Hot Water System Parts & Spares
