Unfortunately there is no way to keep Water Softeners from the damage caused by freezing without properly draining and storing them. Previously we thought you needed to remove them and store in a warm place, but if you follow this procedure, you’ll be fine.
This is actually pretty simple to do if you have a water softener that’s easy to bypass and disconnect like the Clack WS1 valves. You may want to check out one of my other videos on how these systems work here before proceeding https://www.youtube.com/watch?v=OP1DPz81MVA
1) Put the water softener into a regeneration cycle and wait until you hear the unit backwashing water to the drain. Bypass the unit, this will release all of the pressure inside the unit.
2) Advance the water softener through the regeneration cycles until it gets back to the service or home position.
3) Unplug and disconnect the drain line, but be ready to catch some water flowing back from the drain line especially if it drains over head.
4) Shut off the water from the pump and disconnect the water softener inlet and outlet from the household plumbing, be prepared to catch any water that will leak out.
5) You can either put together a series of fittings as shown in the video to blow out the water softener with a compressor or you can lean softener tank over a bucket to remove as much of the water that will flow out. Lay it down until it drains completely, you might actually need to lift the bottom higher than the top to get all of the water out. Plug holes with clean clothes and leave laying down for winter storage.
6) Unscrew the injector cover and drain the water, replace cap.
7) Drain the rest of the house hold plumbing, check my video on Cottage winterizing here. Be sure to open the bypass once all of the plumbing has drained.
When it comes time to re install your softener in the spring, reverse the steps above. Once it is reassembled, bypass the softener before turning the water back on, then put the unit into backwash mode and slowly refill the water softener by partially opening the bypass inlet until you see water flowing to the drain from the drain line. Advance the valve through the regeneration cycles until you get to the service position.
Open a faucet and let water run to drain to remove air, etc. Check for leaks. Then start a complete regeneration cycle until finished and your water softener is back in service.