I have one - & here is what I was instructed to do (by the pool store) and have never had a problem,
You should have 2 pipes in and out with quick connects.
1) Disconnect the pipes
2) blow out the lines (Shop vac etc).
3) Add RV antifreeze in from the top( May have to use had of flex funnel to get it in)
4) Reconnect pipes or seal ( duct tape or another method) so no critters get in
Best of luck.
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