R1234yf pressure temperature chart (PT)
An R1234yf pressure temperature chart (often called a “PT chart”) is a saturation lookup: it tells you what pressure corresponds to boiling/condensing at a given temperature (or the other way around). This is useful for interpreting saturation behavior — but it is not a “normal running pressure” diagnostic chart for an automotive A/C system.
What this table is (and isn’t)
- It is: saturation pressure Psat(T) for R1234yf (two-phase equilibrium).
- It is not: a high-side / low-side “target pressure” table while the system is running.
- It is not: a substitute for OEM service procedures, safety requirements, or local regulation.
If you want the higher-level context first, start here: Refrigerant PT chart (how to read it) and Car A/C pressure chart (why “normal pressures” vary).
Pressure basis: absolute vs gauge
The table below is absolute pressure (kPa(a), bar(a), psi(a)). Many gauges display gauge pressure (relative to ambient). Converting requires local atmospheric pressure:
Patm changes with altitude and weather, so “psig” conversions are never universally correct.
Learn more: Gauge vs absolute pressure (psig vs psia).
R1234yf saturation pressure vs temperature (reference table)
Generated using CoolProp (the same property engine used by FluidTool) at Q=0 saturation (pure fluid; bubble and dew coincide). Values are rounded for readability.
| T (°C) | T (°F) | Psat (kPa(a)) | Psat (bar(a)) | Psat (psi(a)) |
|---|---|---|---|---|
| -20 | -4 | 150.9 | 1.509 | 21.9 |
| -10 | 14 | 221.8 | 2.218 | 32.2 |
| 0 | 32 | 315.8 | 3.158 | 45.8 |
| 10 | 50 | 437.5 | 4.375 | 63.5 |
| 20 | 68 | 591.7 | 5.917 | 85.8 |
| 30 | 86 | 783.5 | 7.835 | 113.6 |
| 40 | 104 | 1018.4 | 10.184 | 147.7 |
| 50 | 122 | 1302.3 | 13.023 | 188.9 |
| 60 | 140 | 1641.9 | 16.419 | 238.1 |
| 70 | 158 | 2044.5 | 20.445 | 296.5 |
How to verify any row in FluidTool
- Open FluidTool with R1234yf selected: /?fluid=R1234yf
- Choose a Two-phase input pair (Temperature & Quality / T + Q).
- Set Q=0 and enter the temperature from the table to read Psat.
For interpretation in a running system, combine saturation with superheat/subcooling concepts — and always follow OEM procedures.
Related
- R1234yf data sheet: basic identifiers and thermodynamic context.
- Refrigerant PT chart: what Tsat(P)/Psat(T) means and common pitfalls.
- Car A/C pressure chart: why “normal pressure” tables are not universal.