if you have blue pex water line in from your water supply then disconnect if it does not have a shut off and either pump RV antifreeze thru to each hot water outlet. Or disconnect same line and low pressure air and turn on each hot water line to it run air not water. When done put in a little RV antifreeze in tank if using air. I put in inline shut off valves so once winterized no fresh water got back into it.
Get the water out now or you will be in for a lot of $$$$.
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