HVAC Toolkit

Pressure-Temperature Charts

Saturation P-T data for common refrigerants

Select Refrigerant

HFC / HCFC

R-22 R-32 R-125 R-134a R-143a R-404A Z R-407C Z R-410A R-507A

Low GWP (HFO)

R-449A Z R-454B Z Low GWP R-513A R-1234yf Low GWP R-1234ze(E) Low GWP

Natural

R-290 (Propane) Low GWP R-600a (Isobutane) Low GWP R-744 (CO2) Low GWP R-717 (NH3) Low GWP

Pressure Unit

psig kPa bar kgf/cm²

R-290

Pure
GWP: 3
ODP: 0
Safety Class: A3

Natural refrigerant with ultra-low GWP. Used in small commercial refrigeration and domestic applications (charge limits apply per IEC 60335-2-89).

A3 HIGHLY FLAMMABLE - Safety Warning

  • ASHRAE 34 Classification: A3 - Non-toxic but HIGHLY FLAMMABLE
  • Maximum charge limits: 150g (sealed systems) per IEC 60335-2-89
  • Use only explosion-proof equipment and tools
  • Work in well-ventilated areas - gas is heavier than air
  • No open flames, sparks, or hot surfaces during service
  • Use hydrocarbon-rated recovery equipment and leak detectors
  • Install gas detection equipment per local codes
Flammability Range: LEL 2.1% - UEL 9.5% in air

Quick P-T Lookup

bar

* Results are interpolated from the P-T table data

Pressure Units: psig = Gauge pressure (relative to atmosphere) kPa / bar / kgf/cm² = Absolute pressure

°C °F bar
-50 -58 0.4
-45 -49 0.5
-40 -40 0.7
-35 -31 1.0
-30 -22 1.3
-25 -13 1.6
-20 -4 2.1
-15 5 2.5
-10 14 3.1
-5 23 3.7
0 32 4.5
5 41 5.3
10 50 6.2
15 59 7.2
20 68 8.3
25 77 9.6
30 86 10.9
35 95 12.4
40 104 14.1
45 113 15.9
50 122 17.8
55 131 19.9
60 140 22.2
65 149 24.7
70 158 27.3
75 167 30.2
80 176 33.3
85 185 36.6
90 194 40.2