How would you refi the HELOC? Don't think its possible to refi it when it is unsecured. By unsecured I mean when the value of the collateral is less than the outstanding loan amount.
When was the last time you received an updated valuation on your home from an agent - not the HELOC lender (they always appraise low).
Remember appraisals are based on what the use for the appraisal is - and it does change the valuation. As a brief example, one of my clients pulled out funds from their home with a HELOC in Sept 2014. The appraisal came in at $260k. I sold the house for him in April 2015 and the sales price was $309k. i ignored the previous HELOC knowing that it was low.
So first, check the value of your home with a good, experienced local Realtor in your area before you do anything.