Sales tax deduction

Is the Sales Tax Deduction Calculator Working?  I paid a ton of sales tax due to a major remodel.  The amount of sales tax I paid exceeds what I paid in State Taxes (approximately $20,000).  No matter what amount I enter, the amount of state tax I owe does not change.  I checked the box "use sales tax" and "change my deduction", but the amount I owe still doesn't change.  Also, I have not paid and I do not owe AMT.  Is anyone having the same problem?