If I own an s Corp and the s corps pay my health insurance do I take a deduction on form 1040? And if I take a deduction on 1040 do I get that exact same amount back in a refund?
Health insurance for a self-employed person (and family) 'established under [the] business' is indeed deductible as an 'adjustment', also called an above-the-line deduction (i.e. before computing AGI). The 1040 instructions for line 29 say how to handle this case (more-than-2% shareholder in an S corp) by reporting the premiums as (imputed) wages and then deducting; effectively you receive the coverage tax-free and it is probably no accident that this is very close to the outright exclusion from income for health insurance (or self-insurance) provided by employer to employee. (Note the version on the website is still for Tax Year 2017; most forms and instructions for TY 2018 won't be available until about November, but this provision will not change as far as we know today.)
This reduces your taxable income; it only reduces your tax according to your marginal tax rate, which depends on where your income falls compared to the bracket amounts for your filing status, which as of this year is 22% 24% or 32% for most people. Whether you get a refund and how much depends on how your total tax (both income tax and self-employment tax, less credits) compares to the amount you prepaid (estimated payments and/or withholding).