Refrigerant R134A Vapor Pressure Table
The vapor pressure tables for every refrigerant is published in the literature for the refrigeration system technicians. This table makes it possible to determine the vapor pressure acting on the column of liquid in a reservoir if the temperature of the reservoir is known.
Since each refrigerant has its own specific vapor pressure table, refrigerant can be identified by measuring the pressure and temperature.
At absolute pressure, "0 bar (0 psi)" corresponds to absolute vacuum. Normal ambient pressure (positive pressure) equals approximately "1 bar (14.5 psi)" absolute pressure. "0 bar (0 psi)" pressure corresponds to an absolute pressure of one bar on most pressure gauges (indicated by "-1 bar (-14.5 psi)" below "0").
Pressure is measured in different units: 1 MPa (mega Pascal) corresponds to 10 bar (145.04 psi) positive pressure or 145 psi. 1 bar (14.5 psi) absolute pressure corresponds to 0 bar (0 psi) positive pressure and thus to the ambient pressure (atmospheric pressure).
| Temperature in °C (°F) | Pressure in bar (psi) of R134a |
|---|---|
| -45 (-49) | -0.61 (-8.85) |
| -40 (-40) | -0.49 (-7.11) |
| -35 (-31) | -0.34 (-4.93) |
| -30 (-22) | -0.16 (-2.32) |
| -25 (-13) | 0.06 (0.87) |
| -20 (-4) | 0.32 (4.64) |
| -15 (-5) | 0.63 (9.14) |
| -10 (14) | 1.00 (14.50) |
| -5 (23) | 1.43 (20.74) |
| 0 (32) | 1.92 (27.85) |
| 5 (41) | 2.49 (36.11) |
| 10 (50) | 3.13 (45.40) |
| 15 (59) | 3.90 (56.57) |
| 20 (68) | 4.70 (68.17) |
| 25 (77) | 5.63 (81.66) |
| 30 (86) | 6.70 (97.18) |
| 35 (95) | 7.83 (113.57) |
| 40 (104) | 9.10 (131.98) |
| 45 (113) | 10.54 (152.87) |
| 50 (122) | 12.11 (175.64) |
| 55 (131) | 13.83 (200.59) |
| 60 (140) | 15.72 (228.00) |
| 65 (149) | 17.79 (258.02) |
| 70 (158) | 20.05 (290.80) |
| 75 (167) | 22.52 (326.63) |
| 80 (176) | 25.21 (362.59) |
| 85 (185) | 28.14 (408.14) |
| 90 (194) | 31.34 (454.55) |