I agree with the Johnstone, Bitzer and Emerson comments for a good PT Chart. All are pretty easy to use and pretty solid. It mainly comes to the user interface you like best.
It is particularly nice to get the exact temperature for the exact pressure or vice versus and not have to go up or down a point or two because your PT Chart Card doesn't have the exact same number that you are seeing.
Do any of you use a PT Calculator for subcooling and superheat? If so, which ones do you like?
Don't mean to be a smart ass but my gauges have a pt chart on em
Yes, but they don't compensate for daylight savings time.
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