Refinanced my primary home in 2012. Pulled out some cash to pay for a second home (not rental). Used part to improve the primary property. How do I enter it in TT2018?

When asked "Was this loan paid off or refinanced with a different lender in 2018?"

Answer "No"

When asked "Is this loan a home equity line of credit or a loan you've ever refinanced?" 

Answer "Yes" and answer the questions that follow which will ask how much cash was taken out and what it was used for. 

Only the amount used for the primary home will count. 

The program will calculate how much of the home loan interest is deductible. 

This is a change resulting from the Tax Cuts and Jobs Act. 

https://www.irs.gov/publications/p936