As you own it outright, yes, it's common to use that to get a HELOC to have enough cash to buy a new home, and then sell your current home. It can be complicated to accurately time everything to line up perfectly so you're under contract and the buyer of your home is closing while you yourself are closing on your new home.

The only risk would be that you need to keep your DTI in check, as you'll be evaluated for your ability to pay your new mortgage with the monthly payment due on the HELOC, regardless if you'll immediately pay it off with the proceeds of the home sale.