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Refrigerant Pressure-Temperature (P/T) Chart

Look up the saturation temperature for a pressure, or the pressure for a temperature, for the most common refrigerants, then scroll the full chart below. Blends show both the dew (vapor) and bubble (liquid) values.

Your numbers

psig
°F

Result

Enter your numbers to see the result.

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Read the how-to guide

5 min read

How to Check Superheat and Subcooling on an AC System

Which reading to charge by, where to clamp, and what high or low superheat and subcooling tell you about the charge.

How to read it

The chart gives the temperature at which the refrigerant boils or condenses at a given pressure. Subtract that from a measured line temperature to get superheat (suction side) or subcooling (liquid side). For single-component refrigerants (R-22, R-32, R-134a) dew and bubble points are the same. For blends, use the dew value for evaporator saturation and the bubble value for condenser saturation.

Pressures are gauge pressure (psig) at sea level. Values come from CoolProp equations of state; R-454B is a calibrated blend model. Verify against manufacturer data for warranty work.

Worked example

R-410A at 118 psig has a saturation temperature of about 40°F. R-22 at 68.5 psig is also about 40°F.

Frequently asked questions

Why do blends show two columns?

Zeotropic blends such as R-454B and R-407C change temperature as they evaporate or condense (glide). Dew is fully vapor; bubble is fully liquid.

Is R-454B the same as R-410A?

No. R-454B runs at slightly lower pressures than R-410A, has a small glide, and is mildly flammable (A2L). Never use R-410A tables for it.

Is the chart in psig or psia?

Gauge pressure (psig). Add 14.7 for absolute pressure at sea level.

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Sample exam questions on this topic

EPA 608

Core, Type I, II and III questions on recovery rules, leak rates and cylinder safety, each with an explanation.

15 questions with explanations

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This calculator gives an estimate for planning and is not tax, legal or engineering advice. Confirm code-related results against the code edition adopted in your jurisdiction and with your authority having jurisdiction, and follow the manufacturer's instructions.