In the US most contemporary industry standard control valves control the volume of water sent to the brine tank and the float assembly is simply a safety device to prevent brine tank overlow in case the control valve malfunctions.

One exception is Kinetico who uses the float valve to set the volume of water in the brine tank. IMO that is a major design flaw in Kinetico's otherwise excellent control valve design because the float is always under water system pressure and more likely to fail which will overflow the brine tank and can result in considerable water damage to the surrounding area.

If you can't get a US online seller to ship you a Fleck 2310 safety float then you can see the parts and details in the parts and details in this picture from a Fleck service manual.

thank you justalurker,

so if I understand it right the floatervalve is not REALLY needed if the automatic control head is programmed to let a certain amount of water into the tank.
the floater valve is just an extra safety device. is that right?

"so if I understand it right the floatervalve is not REALLY needed if the automatic control head is programmed to let a certain amount of water into the tank. the floater valve is just an extra safety device. is that right?"

That is what I said and correct. In the US most softeners are installed inside the house so the float valve is a safety device.

This post was edited by justalurker on Sun, Sep 22, 13 at 12:34