How do water softeners work?

....anyone ????

google ion exchange.

They use a resin that exchanges calcium ions for sdoum ions, thus replacing all te calcium carbonate in the water with sodium carbonate. Calcium carbonate is only marginally soluble and ends up becoming scale,, as well as recacting with sodium stearate (soap) to form a scum..sodium carbonate simply stays soluble, and doesn't react with soap.

Once the resins store of sodium ions is finished, it needs recharging from a strong salt solution. And the exchanged ions (calcium chloride) flushed out.

During this time it is normally either bypassed, or softening switches to a second chamber.

The Natural Philosopher wrote .... "google ion exchange." well, the first line of my post would tend to suggest that that is exactly what I have already done, however reading on a little you would find more.

Thanks to dennis and the philosopher for replying, but if you'd read the post rather than just the title you'd realise that I'd already found that bit out, and was looking for an answer about non-electric softeners, (and also any recommendations or otherwise regarding the Monarch Midi). Thanks, Mike

Presumably they use water pressure to switch between cylinders somehow.

however in a power cut, lack of softened water is hardly high on my list of priorities..

The same way water meters work, hydraulic motors. I didn't think there were electric powered ones. 8-)

nor mine... but installing an extra socket, and the potential (if small) extra running costs are surely worth considering.