R-290 pressure-temperature chart
R-290 pressure-temperature chart with saturation pressure from -40°F to 140°F, generated from CoolProp; bubble and dew columns are shown where applicable.
Quick check: units, range and diagnosis
- Units: temperature is shown in °F with the °C equivalent; pressure is gauge pressure in PSIG at the stated sea-level reference.
- Range: this table covers −40°F through 140°F in 5°F steps. Values outside that range require a separate verified source.
- Diagnostic use: match a stabilized gauge reading with the measured line temperature, then check airflow, operating mode and the manufacturer’s superheat or subcooling procedure. A pressure lookup alone is not a charge or fault diagnosis.
For blends, use the manufacturer’s dew or bubble convention. For single-component refrigerants, the two columns may be identical. Altitude, pressure drop and field safety controls remain outside this lookup.
What this refrigerant PT chart answers
R-290 is propane refrigerant with a high flammability classification and specialized equipment requirements.
This page is maintained by the HVAC Calculator Pro Editorial Team. We publish the inputs, calculation basis and limitations so a technician can reproduce the screening result and decide what must be checked in the field. It is a reference aid, not a substitute for the governing code, a licensed designer or the equipment manufacturer's instructions.
Saturation pressure table
gauge pressure · sea-level reference| Temperature | Equivalent | Bubble PSIG | Dew PSIG |
|---|---|---|---|
| -40 °F | -40.0 °C | 1.4 PSIG | 1.4 PSIG |
| -35 °F | -37.2 °C | 3.4 PSIG | 3.4 PSIG |
| -30 °F | -34.4 °C | 5.7 PSIG | 5.7 PSIG |
| -25 °F | -31.7 °C | 8.1 PSIG | 8.1 PSIG |
| -20 °F | -28.9 °C | 10.7 PSIG | 10.7 PSIG |
| -15 °F | -26.1 °C | 13.6 PSIG | 13.6 PSIG |
| -10 °F | -23.3 °C | 16.7 PSIG | 16.7 PSIG |
| -5 °F | -20.6 °C | 20.1 PSIG | 20.1 PSIG |
| 0 °F | -17.8 °C | 23.7 PSIG | 23.7 PSIG |
| 5 °F | -15.0 °C | 27.6 PSIG | 27.6 PSIG |
| 10 °F | -12.2 °C | 31.8 PSIG | 31.8 PSIG |
| 15 °F | -9.4 °C | 36.3 PSIG | 36.3 PSIG |
| 20 °F | -6.7 °C | 41.1 PSIG | 41.1 PSIG |
| 25 °F | -3.9 °C | 46.3 PSIG | 46.3 PSIG |
| 30 °F | -1.1 °C | 51.8 PSIG | 51.8 PSIG |
| 35 °F | 1.7 °C | 57.7 PSIG | 57.7 PSIG |
| 40 °F | 4.4 °C | 63.9 PSIG | 63.9 PSIG |
| 45 °F | 7.2 °C | 70.6 PSIG | 70.6 PSIG |
| 50 °F | 10.0 °C | 77.6 PSIG | 77.6 PSIG |
| 55 °F | 12.8 °C | 85.1 PSIG | 85.1 PSIG |
| 60 °F | 15.6 °C | 93.0 PSIG | 93.0 PSIG |
| 65 °F | 18.3 °C | 101.4 PSIG | 101.4 PSIG |
| 70 °F | 21.1 °C | 110.2 PSIG | 110.2 PSIG |
| 75 °F | 23.9 °C | 119.5 PSIG | 119.5 PSIG |
| 80 °F | 26.7 °C | 129.3 PSIG | 129.3 PSIG |
| 85 °F | 29.4 °C | 139.7 PSIG | 139.7 PSIG |
| 90 °F | 32.2 °C | 150.5 PSIG | 150.5 PSIG |
| 95 °F | 35.0 °C | 161.9 PSIG | 161.9 PSIG |
| 100 °F | 37.8 °C | 173.9 PSIG | 173.9 PSIG |
| 105 °F | 40.6 °C | 186.5 PSIG | 186.5 PSIG |
| 110 °F | 43.3 °C | 199.6 PSIG | 199.6 PSIG |
| 115 °F | 46.1 °C | 213.4 PSIG | 213.4 PSIG |
| 120 °F | 48.9 °C | 227.8 PSIG | 227.8 PSIG |
| 125 °F | 51.7 °C | 242.9 PSIG | 242.9 PSIG |
| 130 °F | 54.4 °C | 258.7 PSIG | 258.7 PSIG |
| 135 °F | 57.2 °C | 275.1 PSIG | 275.1 PSIG |
| 140 °F | 60.0 °C | 292.3 PSIG | 292.3 PSIG |
How to use this R-290 pressure-temperature chart
- Identify the refrigerant and confirm the unit's design data plate.
- Measure line temperature at the same stable operating point as the gauge pressure.
- Use the chart to translate saturation temperature and then apply the manufacturer's superheat or subcooling procedure.
Worked example: The chart is useful for engineering reference, not for selecting charge quantity, work area controls or replacement components. Only trained personnel using approved A3 equipment and recovery procedures should service an R-290 system.
Record the result with the project address, equipment model, code edition and assumptions. That audit trail is more useful than copying a single number without its conditions.
Continue with the right tool
What is specific to R-290
Flammability, charge limits, ventilation and electrical ignition controls are separate safety decisions from saturation pressure.
Safety and climate profile: Safety classification A3; approximate 100-year GWP 3; flammability controls and charge limits are mandatory.
PSIG is gauge pressure. Absolute pressure adds local atmospheric pressure, so a gauge reading cannot be compared directly with an absolute-pressure chart without conversion.
For the governing safety and refrigerant-transition context, consult the U.S. EPA refrigerant guidance and the equipment manufacturer documentation.
Use boundary: This table does not model line pressure drop, superheat, subcooling, altitude correction or field safety controls. Confirm the correct blend basis and dew/bubble convention before using it.
Common questions
Can I use the R-290 pressure alone to charge a system?
No. Pressure must be interpreted with line temperature, airflow, operating mode and the manufacturer's charging method.
Why does this R-290 page say bubble point?
Bubble point is the saturated-liquid reference used by this generated table. Zeotropic blends may also require a dew-point reference, so the service procedure controls.
Cite or reuse this table
This dataset is free to cite, quote and redistribute with attribution. Use the stable URL below — it does not change when the table is regenerated.
HVAC Calculator Pro. (2026-10-07). R-290 Pressure Temperature Chart (-40°F to 140°F Printable). Retrieved from https://hvaccalcpro.com/refrigerants/r-290-pt-charthttps://hvaccalcpro.com/refrigerants/r-290-pt-chart