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How to reach PT Charts: report a chart value that disagrees with your manufacturer's chart, a changed EPA rule or a broken page.
Updated
Messages go to Paul Gunder, who builds the site and its charts.
When a chart value disagrees with a manufacturer's chart, please send that chart, or a link to it, along with the refrigerant and the row: the temperature, and the pressure each chart gives. That's enough to recheck the point against CoolProp and the reference charts.
When an EPA rule changes, the Federal Register notice is the most useful thing to send, since the practice questions are only updated from the rule text itself.
Broken pages, wrong links and typos are welcome too.