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Refrigerant PT Chart

A PT chart shows the pressure a refrigerant sits at for a given temperature when it's saturated, with liquid and vapor together. Techs use it to check superheat and subcooling.

Charts coming. We publish pressure-temperature values only from manufacturer data we have the right to reproduce, and that isn't in place yet. Until then, use the PT data published by your refrigerant's manufacturer. This page isn't listed in search results until the charts are added.

R-22 PT chart

R-22 is an HCFC (EPA test topics) and a high-pressure refrigerant under EPA's definitions (82.152). Chart to come.

R-410A PT chart

R-410A is a high-pressure refrigerant under EPA's definitions (82.152). Chart to come.

R-454B PT chart

R-454B is an A2L blend (EPA GreenChill slides). For blends, a chart lists two values at each temperature: the bubble point (liquid) and the dew point (vapor). Chart to come.

R-32 PT chart

R-32 is an A2L refrigerant (EPA GreenChill slides). Chart to come.

How to read a PT chart

  1. Find your refrigerant's column.
  2. Find the temperature row. The value is the saturation pressure, usually in psig.
  3. Gauges read psig. To convert to psia, add 14.7 (EPA test topics).
  4. Compare the saturation temperature with the actual line temperature: above it on the suction line is superheat, below it on the liquid line is subcooling.

Studying for the EPA 608?

Pressure-temperature relationships are on the Type I, Type II and Type III outlines (EPA test topics). Practice them: Type 2 practice test · free EPA 608 practice test · A2L refrigerants.