Is it possible to consolidate a first mortgage and a home equity line of credit into one fixed rate loan?

Maybe. You would have to refinance you existing mortage, then pay off you HELOC. Unless you can get a loan with NO closing costs at the same or lesser interest rate, ti doesn't make sense. It might take you 10 years to break even. Since you can use the interest from both loans as a deduction on your taxes, it doesn't make sense to me.