I'm trying to help a friend with a small project in which we are wanting to take R717 pressure and convert it to temperature, in a building automation system. My background is not one of refrigeration unfortunately, but I intend on writing code in the automation system to accomplish this.

I understand how the P/T chart works, but as far as developing a formula that I can interpret to code is where I am having issues.

I tried to import a P/T chart into Excel and plot out a graph and capture the formula, but my Excel/Math skills aren't quite where they need to be.

Anyone have any good suggestions on figuring out a formula for this?

Thanks,