I live in Illinois and want to know how to prepare my heat pump for the winter?

Thank you for writing. The best thing to do if follow your manufacturers procedure that is in most owners manuals. If that isn’t an option then I would disconnect the water pipes and put a wet vac on each pipe on the heat pump and suck out any remaining water. Then squirt some recreational vehicle anti-freeze in the pipes as insurance. Then I would cover the heat pump with a tarp to keep the snow and leaves out. Don’t complete cover the heat pumps sides as then you make a small solar rodent vacation home for the winter. A better option is to buy a custom cut winter swimming pool heat pump cover from me that will be hand made for your model. they don’t get any better than that.